Text::CSV(3)
okay bestie, welcome to the Text::CSV(3) page from the User Contributed Perl Documentation 💖
🎀 NAME 🎀
Text::CSV — comma-separated values manipulator (using XS or PurePerl).
✨ SYNOPSIS ✨
This section is taken from Text::CSV_XS.
# Functional interface
use Text::CSV qw( csv );
# Read whole file in memory
my $aoa = csv (in => "data.csv"); # as array of array
my $aoh = csv (in => "data.csv",
headers => "auto"); # as array of hash
# Write array of arrays as csv file
csv (in => $aoa, out => "file.csv", sep_char => ";");
# Only show lines where "code" is odd
csv (in => "data.csv", filter => { code => sub { $_ % 2 }});
# Object interface
use Text::CSV;
my @rows;
# Read/parse CSV
my $csv = Text::CSV->new ({ binary => 1, auto_diag => 1 });
open my $fh, "<:encoding(utf8)", "test.csv" or die "test.csv: $!";
while (my $row = $csv->getline ($fh)) {
$row->[2] =~ m/pattern/ or next; # 3rd field should match
push @rows, $row;
}
close $fh;
# and write as CSV
open $fh, ">:encoding(utf8)", "new.csv" or die "new.csv: $!";
$csv->say ($fh, $_) for @rows;
close $fh or die "new.csv: $!";💖 DESCRIPTION 💖
Text::CSV is a thin wrapper for Text::CSV_XS-compatible modules now. All the backend modules provide facilities for the composition and decomposition of comma-separated values. Text::CSV uses Text::CSV_XS by default, and when Text::CSV_XS is not available, falls back on Text::CSV_PP, which is bundled in the same distribution as this module.
🌈 CHOOSING BACKEND 🌈
This module respects an environmental variable called PERL_TEXT_CSV when it decides a backend module to use. If this environmental variable is not set, it tries to load Text::CSV_XS, and if Text::CSV_XS is not available, falls back on Text::CSV_PP;
If you always don't want it to fall back on Text::CSV_PP, set the variable like this (export may be setenv, set and the likes, depending on your environment):
> export PERL_TEXT_CSV=Text::CSV_XSIf you prefer Text::CSV_XS to Text::CSV_PP (default), then:
> export PERL_TEXT_CSV=Text::CSV_XS,Text::CSV_PPYou may also want to set this variable at the top of your test files, in order not to be bothered with incompatibilities between backends (you need to wrap this in BEGIN, and set before actually use-ing Text::CSV module, as it decides its backend as soon as it's loaded):
BEGIN { $ENV{PERL_TEXT_CSV}='Text::CSV_PP'; }
use Text::CSV;🦋 NOTES 🦋
This section is also taken from Text::CSV_XS.
🌸 Embedded newlines 🌸
Important Note: The default behavior is to accept only ASCII characters in the range from 0x20 (space) to 0x7E (tilde). This means that the fields can not contain newlines. If your data contains newlines embedded in fields, or characters above 0x7E (tilde), or binary data, you must set binary => 1 in the call to new. To cover the widest range of parsing options, you will always want to set binary.
But you still have the problem that you have to pass a correct line to the parse method, which is more complicated from the usual point of usage:
my $csv = Text::CSV->new ({ binary => 1, eol => $/ });
while (<>) { # WRONG!
$csv->parse ($_);
my @fields = $csv->fields ();
}this will break, as the while might read broken lines: it does not care about the quoting. If you need to support embedded newlines, the way to go is to not pass eol in the parser (it accepts "\n", "\r", and "\r\n" by default) and then
my $csv = Text::CSV->new ({ binary => 1 });
open my $fh, "<", $file or die "$file: $!";
while (my $row = $csv->getline ($fh)) {
my @fields = @$row;
}The old(er) way of using global file handles is still supported
while (my $row = $csv->getline (*ARGV)) { ... }🧚 Unicode 🧚
Unicode is only tested to work with perl-5.8.2 and up.
See also BOM.
The simplest way to ensure the correct encoding is used for in- and output is by either setting layers on the filehandles, or setting the encoding argument for csv.
open my $fh, "<:encoding(UTF-8)", "in.csv" or die "in.csv: $!";or
my $aoa = csv (in => "in.csv", encoding => "UTF-8");open my $fh, ">:encoding(UTF-8)", "out.csv" or die "out.csv: $!";or
csv (in => $aoa, out => "out.csv", encoding => "UTF-8");On parsing (both for getline and parse), if the source is marked being UTF8, then all fields that are marked binary will also be marked UTF8.
On combining (print and combine): if any of the combining fields was marked UTF8, the resulting string will be marked as UTF8. Note however that all fields before the first field marked UTF8 and contained 8-bit characters that were not upgraded to UTF8, these will be bytes in the resulting string too, possibly causing unexpected errors. If you pass data of different encoding, or you don't know if there is different encoding, force it to be upgraded before you pass them on:
$csv->print ($fh, [ map { utf8::upgrade (my $x = $_); $x } @data ]);For complete control over encoding, please use Text::CSV::Encoded:
use Text::CSV::Encoded;
my $csv = Text::CSV::Encoded->new ({
encoding_in => "iso-8859-1", # the encoding comes into Perl
encoding_out => "cp1252", # the encoding comes out of Perl
});
$csv = Text::CSV::Encoded->new ({ encoding => "utf8" });
# combine () and print () accept *literally* utf8 encoded data
# parse () and getline () return *literally* utf8 encoded data
$csv = Text::CSV::Encoded->new ({ encoding => undef }); # default
# combine () and print () accept UTF8 marked data
# parse () and getline () return UTF8 marked data🎀 BOM 🎀
BOM (or Byte Order Mark) handling is available only inside the header method. This method supports the following encodings: utf-8, utf-1, utf-32be, utf-32le, utf-16be, utf-16le, utf-ebcdic, scsu, bocu-1, and gb-18030. See Wikipedia at https://en.wikipedia.org/wiki/Byte_order_mark.
If a file has a BOM, the easiest way to deal with that is
my $aoh = csv (in => $file, detect_bom => 1);All records will be encoded based on the detected BOM.
This implies a call to the header method, which defaults to also set the column_names. So this is not the same as
my $aoh = csv (in => $file, headers => "auto");which only reads the first record to set column_names but ignores any meaning of possible present BOM.
👑 METHODS 👑
This section is also taken from Text::CSV_XS.
⭐ version ⭐
(Class method) Returns the current module version.
💜 new 💜
(Class method) Returns a new instance of class Text::CSV. The attributes are described by the (optional) hash ref \%attr.
my $csv = Text::CSV->new ({ attributes ... });The following attributes are available:
🍓 eol 🍓
my $csv = Text::CSV->new ({ eol => $/ });
$csv->eol (undef);
my $eol = $csv->eol;The end-of-line string to add to rows for print or the record separator for getline.
When not passed in a parser instance, the default behavior is to accept "\n", "\r", and "\r\n", so it is probably safer to not specify eol at all. Passing undef or the empty string behave the same.
When not passed in a generating instance, records are not terminated at all, so it is probably wise to pass something you expect. A safe choice for eol on output is either $/ or "\r\n".
Common values for eol are "\012" ("\n" or Line Feed), "\015\012" ("\r\n" or Carriage Return, Line Feed), and "\015" ("\r" or Carriage Return). The eol attribute cannot exceed 7 (ASCII) characters.
If both $/ and eol equal "\015", parsing lines that end on only a Carriage Return without Line Feed, will be parsed correct.
💅 eol_type 💅
my $eol = $csv->eol_type;This read-only method returns the internal state of what is considered the valid EOL for parsing.
🫶 sep_char 🫶
my $csv = Text::CSV->new ({ sep_char => ";" });
$csv->sep_char (";");
my $c = $csv->sep_char;The char used to separate fields, by default a comma. (,). Limited to a single-byte character, usually in the range from 0x20 (space) to 0x7E (tilde). When longer sequences are required, use sep.
The separation character can not be equal to the quote character or to the escape character.
😭 sep 😭
my $csv = Text::CSV->new ({ sep => "\N{FULLWIDTH COMMA}" });
$csv->sep (";");
my $sep = $csv->sep;The chars used to separate fields, by default undefined. Limited to 8 bytes.
When set, overrules sep_char. If its length is one byte it acts as an alias to sep_char.
🔥 quote_char 🔥
my $csv = Text::CSV->new ({ quote_char => "'" });
$csv->quote_char (undef);
my $c = $csv->quote_char;The character to quote fields containing blanks or binary data, by default the double quote character ("""). A value of undef suppresses quote chars (for simple cases only). Limited to a single-byte character, usually in the range from 0x20 (space) to 0x7E (tilde). When longer sequences are required, use quote.
quote_char can not be equal to sep_char.
🌟 quote 🌟
my $csv = Text::CSV->new ({ quote => "\N{FULLWIDTH QUOTATION MARK}" });
$csv->quote ("'");
my $quote = $csv->quote;The chars used to quote fields, by default undefined. Limited to 8 bytes.
When set, overrules quote_char. If its length is one byte it acts as an alias to quote_char.
This method does not support undef. Use quote_char to disable quotation.
💀 escape_char 💀
my $csv = Text::CSV->new ({ escape_char => "\\" });
$csv->escape_char (":");
my $c = $csv->escape_char;The character to escape certain characters inside quoted fields. This is limited to a single-byte character, usually in the range from 0x20 (space) to 0x7E (tilde).
The escape_char defaults to being the double-quote mark ("""). In other words the same as the default quote_char. This means that doubling the quote mark in a field escapes it:
"foo","bar","Escape ""quote mark"" with two ""quote marks""","baz"If you change the quote_char without changing the escape_char, the escape_char will still be the double-quote ("""). If instead you want to escape the quote_char by doubling it you will need to also change the escape_char to be the same as what you have changed the quote_char to.
Setting escape_char to undef or "" will completely disable escapes and is greatly discouraged. This will also disable escape_null.
The escape character can not be equal to the separation character.
🙈 binary 🙈
my $csv = Text::CSV->new ({ binary => 1 });
$csv->binary (0);
my $f = $csv->binary;okay so let's keep going with the attributes, bestie, we're in the thick of it now 💅
When binary is set to 1, you're allowed to have binary characters chilling inside quoted fields — and yes that includes line feeds, carriage returns and "NULL" bytes. (That last one could be escaped as ""0" if you're feeling fancy.) By default this whole feature is off. 🚫
But here's the lil plot twist: if a string is marked UTF8, binary gets turned on automatically the moment binary characters other than CR and NL show up. And ngl, a simple string like "\x{00a0}" might still be binary but not marked UTF8 — so setting { binary => 1 } is still a wise option. lowkey just do it. 💡
strict
my $csv = Text::CSV->new ({ strict => 1 });
$csv->strict (0);
my $f = $csv->strict;Set this one to 1 and any row that parses to a different number of fields than the previous row will make the parser throw error 2014. consistency is literally the vibe check here. 🚨
Empty rows, or rows that result in no fields (like comment lines), are exempt from these checks — they get a free pass, no questions asked. ✨
strict_eol
my $csv = Text::CSV->new ({ strict_eol => 1 });
$csv->strict_eol (0);
my $f = $csv->strict_eol;Three moods, bestie, pick your fighter:
- Set it to
0and no EOL consistency checks happen at all. zero drama. 🦋 - Set it to
1and any row that parses with an EOL other than the EOL from the first row will cause a warning. The error gets ignored and parsing continues. This warning is only thrown once. But heads up: in data with various different line endings,"\r\r"will still throw an error that cannot be ignored. 😭 - Set it to
2or higher and any row that parses with an EOL other than the EOL from the first row will cause error2016to be thrown. And fair warning — the line being parsed to this error might not be stored in the result. 💀
skip_empty_rows
my $csv = Text::CSV->new ({ skip_empty_rows => 1 });
$csv->skip_empty_rows ("eof");
my $f = $csv->skip_empty_rows;This attribute defines the behavior for empty rows — meaning an "eol" immediately following the start of line. Default behavior is to return one single empty field.
It's only used in parsing, and it's ineffective when using "parse" and "fields". (iykyk 🫶)
Possible values for this attribute are:
0 | undef
my $csv = Text::CSV->new ({ skip_empty_rows => 0 });
$csv->skip_empty_rows (undef);No special action is taken. The result will be one single empty field. classic.
1 | "skip"
my $csv = Text::CSV->new ({ skip_empty_rows => 1 });
$csv->skip_empty_rows ("skip");The row will be skipped. bye bestie 👋
2 | "eof" | "stop"
my $csv = Text::CSV->new ({ skip_empty_rows => 2 });
$csv->skip_empty_rows ("eof");The parsing will stop as if an "eof" was detected. 🛑
3 | "die"
my $csv = Text::CSV->new ({ skip_empty_rows => 3 });
$csv->skip_empty_rows ("die");The parsing will stop. The internal error code will be set to 2015 and the parser will "die". dramatic, honestly. 💀
4 | "croak"
my $csv = Text::CSV->new ({ skip_empty_rows => 4 });
$csv->skip_empty_rows ("croak");The parsing will stop. The internal error code will be set to 2015 and the parser will "croak". same energy, different frog. 🐸
5 | "error"
my $csv = Text::CSV->new ({ skip_empty_rows => 5 });
$csv->skip_empty_rows ("error");The parsing will fail. The internal error code will be set to 2015.
callback
my $csv = Text::CSV->new ({ skip_empty_rows => sub { [] } });
$csv->skip_empty_rows (sub { [ 42, $., undef, "empty" ] });The callback is invoked and its result gets used instead. If you want the parse to stop after the callback, make sure to return a false value — that's the whole trick. 🎀
The returned value from the callback should be an array-ref. Any other type will cause the parse to stop, so these two are equivalent in behavior:
csv (in => $fh, skip_empty_rows => "stop");
csv (in => $fh. skip_empty_rows => sub { 0; });Without arguments, the current value is returned: 0, 1, "eof", "die", "croak" or the callback. getter mode activated ✨
formula_handling
Alias for "formula". that's it, that's the whole section 🎀
formula
my $csv = Text::CSV->new ({ formula => "none" });
$csv->formula ("none");
my $f = $csv->formula;This defines the behavior of fields containing formulas. Since formulas are considered dangerous in spreadsheets (main character villain energy fr), this attribute can define an optional action to be taken if a field starts with an equal sign ("="). 🧨
For purpose of code-readability, this can also be written as:
my $csv = Text::CSV->new ({ formula_handling => "none" });
$csv->formula_handling ("none");
my $f = $csv->formula_handling;Possible values for this attribute are:
none
Take no specific action. This is the default.
$csv->formula ("none");die
Cause the process to "die" whenever a leading "=" is encountered.
$csv->formula ("die");croak
Cause the process to "croak" whenever a leading "=" is encountered. (See Carp.)
$csv->formula ("croak");diag
Report position and content of the field whenever a leading "=" is found. The value of the field is unchanged — it just snitches. 👀
$csv->formula ("diag");empty
Replace the content of fields that start with a "=" with the empty string.
$csv->formula ("empty");
$csv->formula ("");undef
Replace the content of fields that start with a "=" with undef.
$csv->formula ("undef");
$csv->formula (undef);a callback
Modify the content of fields that start with a "=" with the return-value of the callback. The original content of the field is available inside the callback as $_. obsessed with this level of control 💅
# Replace all formula's with 42
$csv->formula (sub { 42; });
# same as $csv->formula ("empty") but slower
$csv->formula (sub { "" });
# Allow =4+12
$csv->formula (sub { s/^=(\d+\+\d+)$/$1/eer });
# Allow more complex calculations
$csv->formula (sub { eval { s{^=([-+*/0-9()]+)$}{$1}ee }; $_ });All other values will give a warning and then fallback to "diag". so cute of it to have a safety net 🥺
decode_utf8
my $csv = Text::CSV->new ({ decode_utf8 => 1 });
$csv->decode_utf8 (0);
my $f = $csv->decode_utf8;This attribute defaults to TRUE. ✅
While parsing, fields that are valid UTF-8 are automatically set to be UTF-8, so that
$csv->parse ("\xC4\xA8\n");results in
PV("\304\250"\0) [UTF8 "\x{128}"]Sometimes it might not be a desired action. To prevent those upgrades, set this attribute to false, and the result will be
PV("\304\250"\0)no glow-up for you, string. 🙈
auto_diag
my $csv = Text::CSV->new ({ auto_diag => 1 });
$csv->auto_diag (2);
my $l = $csv->auto_diag;Set this attribute to a number between 1 and 9 and it causes "error_diag" to be automatically called in void context upon errors. auto-pilot diagnostics, we love to see it ✨
In case of error 2012 - EOF, this call will be void. (special little exception, don't worry about it 💖)
If "auto_diag" is set to a numeric value greater than 1, it will "die" on errors instead of "warn". If set to anything unrecognized, it will be silently ignored. rude but okay 🙃
Future extensions to this feature will include more reliable auto-detection of "autodie" being active in the scope of which the error occurred which will increment the value of "auto_diag" with 1 the moment the error is detected. future plans, bestie, we'll see 🌈
diag_verbose
my $csv = Text::CSV->new ({ diag_verbose => 1 });
$csv->diag_verbose (2);
my $l = $csv->diag_verbose;Set the verbosity of the output triggered by "auto_diag". Currently it only adds the current input-record-number (if known) to the diagnostic output with an indication of the position of the error. more context = more slay 🔍
blank_is_undef
my $csv = Text::CSV->new ({ blank_is_undef => 1 });
$csv->blank_is_undef (0);
my $f = $csv->blank_is_undef;Under normal circumstances, "CSV" data makes no distinction between quoted- and unquoted empty fields. These both end up in an empty string field once read, thus
1,"",," ",2is read as
("1", "", "", " ", "2")When writing "CSV" files with either "always_quote" or "quote_empty" set, the unquoted empty field is the result of an undefined value. To enable this distinction when reading "CSV" data, the "blank_is_undef" attribute will cause unquoted empty fields to be set to undef, causing the above to be parsed as
("1", "", undef, " ", "2")Note that this is specifically important when loading "CSV" fields into a database that allows "NULL" values, as the perl equivalent for "NULL" is undef in DBI land. so if you're doing database things, this is your girl 🫶
empty_is_undef
my $csv = Text::CSV->new ({ empty_is_undef => 1 });
$csv->empty_is_undef (0);
my $f = $csv->empty_is_undef;Going one step further than "blank_is_undef" (she said "hold my strawberry juice" 🍓), this attribute converts all empty fields to undef, so
1,"",," ",2is read as
(1, undef, undef, " ", 2)Note that this affects only fields that are originally empty, not fields that are empty after stripping allowed whitespace. YMMV. 💫
allow_whitespace
my $csv = Text::CSV->new ({ allow_whitespace => 1 });
$csv->allow_whitespace (0);
my $f = $csv->allow_whitespace;When this option is set to true, the whitespace ("TAB"'s and "SPACE"'s) surrounding the separation character is removed when parsing. If either "TAB" or "SPACE" is one of the three characters "sep_char", "quote_char", or "escape_char" it will not be considered whitespace. rules are rules ✨
Now lines like:
1 , "foo" , bar , 3 , zappare parsed as valid "CSV", even though it violates the "CSV" specs. chaotic but we move 🦋
Note that all whitespace is stripped from both start and end of each field. That would make it more than a feature to enable parsing bad "CSV" lines, as
1, 2.0, 3, ape , monkeywill now be parsed as
("1", "2.0", "3", "ape", "monkey")even if the original line was perfectly acceptable "CSV". so like… she's a little aggressive about it 😭
allow_loose_quotes
my $csv = Text::CSV->new ({ allow_loose_quotes => 1 });
$csv->allow_loose_quotes (0);
my $f = $csv->allow_loose_quotes;By default, parsing unquoted fields containing "quote_char" characters like
1,foo "bar" baz,42would result in parse error 2034. Though it is still bad practice to allow this format, we cannot help the fact that some vendors make their applications spit out lines styled this way. not our fault, not our problem 🙈
If there is really bad "CSV" data, like
1,"foo "bar" baz",42or
1,""foo bar baz"",42there is a way to get this data-line parsed and leave the quotes inside the quoted field as-is. This can be achieved by setting "allow_loose_quotes" AND making sure that the "escape_char" is not equal to "quote_char". both conditions, bestie, no skipping steps 💅
allow_loose_escapes
my $csv = Text::CSV->new ({ allow_loose_escapes => 1 });
$csv->allow_loose_escapes (0);
my $f = $csv->allow_loose_escapes;Parsing fields that have "escape_char" characters that escape characters that do not need to be escaped, like:
would give you, like, parse error 2025 😭 and while it's honestly bad practice to let that format slide, this attribute lets you treat all escape character sequences as equal. no cap.
🦋 allow_unquoted_escape
my $csv = Text::CSV->new ({ allow_unquoted_escape => 1 });
$csv->allow_unquoted_escape (0);
my $f = $csv->allow_unquoted_escape;okay so there's this whole backward-compatibility thing where escape_char being different from quote_char means escape_char literally cannot sit in the first position of a field. like, if quote_char is the default " and escape_char is set to \, this right here would be illegal:
1,\0,2setting this attribute to 1 might help you get around those backward-compat issues and let that style through. might. we're being honest here. ✨
🎀 always_quote
my $csv = Text::CSV->new ({ always_quote => 1 });
$csv->always_quote (0);
my $f = $csv->always_quote;by default the generated fields only get quoted if they need to be — like if they contain the separator character. if you set this to 1, then all defined fields get quoted. (undef fields do not get quoted, peep "blank_is_undef".) this one's lowkey iconic because it makes exported data so much easier to handle in external applications. periodt.
🌸 quote_space
my $csv = Text::CSV->new ({ quote_space => 1 });
$csv->quote_space (0);
my $f = $csv->quote_space;default behavior: a space in a field triggers quotation. there's literally no rule in CSV forcing that, nor any rule against it, so the default is true — for safety 💅. you can remove space from the trigger list by setting this to 0.
🧚 quote_empty
my $csv = Text::CSV->new ({ quote_empty => 1 });
$csv->quote_empty (0);
my $f = $csv->quote_empty;again, generated fields only get quoted when they need it, and an empty (defined) field doesn't need quotation. set this to 1 and empty defined fields will be quoted. (undef fields are still not quoted, see "blank_is_undef".) also go look at "always_quote".
💜 quote_binary
my $csv = Text::CSV->new ({ quote_binary => 1 });
$csv->quote_binary (0);
my $f = $csv->quote_binary;by default, every "unsafe" byte inside a string makes the whole combined field get quoted. set this to 0 and you can disable that trigger for bytes >= 0x7F. slay.
⭐ escape_null
my $csv = Text::CSV->new ({ escape_null => 1 });
$csv->escape_null (0);
my $f = $csv->escape_null;so by default a NULL byte in a field gets escaped. this option lets you treat the NULL byte as just a plain binary character in binary mode (that's when { binary => 1 } is set). default is true. you can stop NULL escapes by setting this attribute to 0.
when the escape_char attribute is set to undefined, this attribute gets set to false. just so you know 👑
the default setting will encode =\x00= as
"="0="with escape_null set, that turns into
"=\x00="the default when you're using the csv function is false.
for backward-compatibility reasons, the deprecated old name quote_null is still recognized. iykyk 🙈
🫶 keep_meta_info
my $csv = Text::CSV->new ({ keep_meta_info => 1 });
$csv->keep_meta_info (0);
my $f = $csv->keep_meta_info;by default, parsing input records is as simple and as fast as physically possible — which is great, except some parsing info (like whether the original field was quoted) just gets yeeted in the process 😭. setting this flag to true lets you retrieve that info after parsing, using "meta_info", "is_quoted", and "is_binary" (described below). default is false, for performance.
and here's the fun part: if you set this attribute to a value greater than 9, you get to control the output quotation style to match how it was used in the input of the last parsed record — unless quotation got added for other reasons. main character energy tbh:
my $csv = Text::CSV->new ({
binary => 1,
keep_meta_info => 1,
quote_space => 0,
});
my $row = $csv->parse (q{1,,"", ," ",f,"g","h""h",help,"help"});
$csv->print (*STDOUT, \@row);
# 1,,, , ,f,g,"h""h",help,help
$csv->keep_meta_info (11);
$csv->print (*STDOUT, \@row);
# 1,,"", ," ",f,"g","h""h",help,"help"🍓 undef_str
my $csv = Text::CSV->new ({ undef_str => "\\N" });
$csv->undef_str (undef);
my $s = $csv->undef_str;this one optionally defines what undefined fields output as. heads up: the value you pass is not changed at all — so if it needs quotation, you gotta include the quotation inside the attribute value yourself. use with caution bestie, because passing a value like ",",,,,""" will for sure mess up your output 💀. default for this attribute is undef, meaning no special treatment.
it's genuinely useful when you're exporting CSV data to be imported into custom loaders (like for MySQL) that recognize special sequences for NULL data.
this attribute has no meaning when parsing CSV data. none. zero.
🌈 comment_str
my $csv = Text::CSV->new ({ comment_str => "#" });
$csv->comment_str (undef);
my $s = $csv->comment_str;optionally defines a string that gets recognized as a comment. if this attribute is defined, every line starting with that sequence gets skipped as a comment instead of being parsed as CSV. iconic for skipping headers ngl.
this attribute has no meaning when generating CSV.
comment strings that start with any of the special characters/sequences are not supported — so it cannot start with any ofsep_char,quote_char,escape_char,sep,quote, oreol. don't do it 🙈
for convenience, comment is an alias for comment_str. 🎀
🔥 verbatim
my $csv = Text::CSV->new ({ verbatim => 1 });
$csv->verbatim (0);
my $f = $csv->verbatim;okay this one is a quite controversial attribute to set, but it makes some hard things possible. very "hear me out" of it.
the rationale: tell the parser that the normally special characters newline (NL) and Carriage Return (CR) are not special when this flag is set, and get dealt with as ordinary binary characters. this eases working with data that has embedded newlines.
when "verbatim" is used with "getline", "getline" auto-chomp's every line.
imagine a file format like
M^^Hans^Janssen^Klas 2\n2A^Ja^11-06-2007#\r\nwhere the line ending is a very specific #\r\n, and the sep_char is a ^ (caret). none of the fields are quoted, but embedded binary data is likely hanging around. with that specific line ending, this shouldn't be too hard to detect.
by default, Text::CSV's parse function is instructed to only know about \n and \r as legal line endings — so it has to deal with an embedded newline as a real "end-of-line", and it can scan the next line if binary is true and the newline is inside a quoted field. with this option, we tell "parse" to parse the line as if \n is literally nothing more than a binary character. the way that changes everything 😭
for "parse" this means the parser has no more idea about line ending, and "getline" chomp's line endings on reading.
💖 types
a set of column types; the attribute is immediately passed to the "types" method.
🦋 callbacks
see the "Callbacks" section below.
👑 accessors
to sum it up, bestie:
$csv = Text::CSV->new ();is equivalent to
$csv = Text::CSV->new ({
eol => undef, # \r, \n, or \r\n
sep_char => ',',
sep => undef,
quote_char => '"',
quote => undef,
escape_char => '"',
binary => 0,
decode_utf8 => 1,
auto_diag => 0,
diag_verbose => 0,
blank_is_undef => 0,
empty_is_undef => 0,
allow_whitespace => 0,
allow_loose_quotes => 0,
allow_loose_escapes => 0,
allow_unquoted_escape => 0,
always_quote => 0,
quote_empty => 0,
quote_space => 1,
escape_null => 1,
quote_binary => 1,
keep_meta_info => 0,
strict => 0,
skip_empty_rows => 0,
formula => 0,
verbatim => 0,
undef_str => undef,
comment_str => undef,
types => undef,
callbacks => undef,
});for all of those flags up there, there's an accessor method waiting for you — ask it what the current value is, or change the value:
my $quote = $csv->quote_char;
$csv->binary (1);it is not wise to change these settings halfway through writingCSVdata to a stream. but if you wanna create a new stream using the availableCSVobject? no harm in changing them. 💅
if the "new" constructor call fails, it returns undef and makes the fail reason available through the "error_diag" method.
$csv = Text::CSV->new ({ ecs_char => 1 }) or
die "".Text::CSV->error_diag ();"error_diag" will return a string like
"INI - Unknown attribute 'ecs_char'"🌟 known_attributes
@attr = Text::CSV->known_attributes;
@attr = Text::CSV::known_attributes;
@attr = $csv->known_attributes;this method returns an ordered list of all the supported attributes described above. super useful for knowing what attributes are valid in classes that use or extend Text::CSV. iykyk 🫶
$status = $csv->print ($fh, $colref);basically "combine" + "string" + "print", except way more efficient. it expects an array ref as input (not an array!) and the resulting string isn't actually created — it's immediately written to the $fh object, which is typically an IO handle or any other object that offers a print method. ate and left no crumbs 🔥
for performance reasons, "print" doesn't create a result string, so "string", "status", "fields", and "error_input" methods will all return undefined information after you execute this method. so like, don't go looking for them. 💀
if $colref is undef (explicitly, not through a variable argument) and "bind_columns" was used to specify the fields to be printed, you can get some performance improvements — otherwise the data would have to be copied as arguments to the method call:
$csv->bind_columns (\($foo, $bar));
$status = $csv->print ($fh, undef);a short benchmark, for the numbers girlies:
my @data = ("aa" .. "zz");
$csv->bind_columns (\(@data));
$csv->print ($fh, [ @data ]); # 11800 recs/sec
$csv->print ($fh, \@data ); # 57600 recs/sec
$csv->print ($fh, undef ); # 48500 recs/sec🎀 say
$status = $csv->say ($fh, $colref);like "print", but eol defaults to $\. cute little one-liner energy ✨
💫 print_hr
$csv->print_hr ($fh, $ref);(and the tea continues, bestie — we are literally not done here 💅)
okay bestie so this one is literally just a wrapper — a cute lil' convenience layer with basic parameter checks sitting on top of this:
$csv->print ($fh, [ map { $ref->{$_} } $csv->column_names ]);like, that's the whole vibe. it prints your $ref using the column order you already set with column_names, no cap 💅
✨ combine ✨
$status = $csv->combine (@fields);this one builds a whole CSV record out of @fields and gives you back success or failure, periodt.
it can fail if there are no arguments at all, or if some argument contains an invalid character 😭
on success? call string and boom, you've got your CSV string. on failure, string gives you back undef and you can hit up error_input to see which argument was the problem child 🙈
🌸 string 🌸
$line = $csv->string ();returns whichever was called most recently: the input you fed to parse, or the CSV string that came out of combine. that's it, that's the method 🎀
🦋 getline 🦋
$colref = $csv->getline ($fh);this is the counterpart to print, the way parse is the counterpart to combine 💖
it parses one row from the $fh handle using the getline method that belongs to $fh, and parses that row into an array ref. you get that array ref back, or undef if it failed. and if $fh doesn't support getline, bestie... you're probably gonna hit errors 😬
heads up: when fields are bound with bind_columns, the return value is a reference to an empty list.
and after this, the string, fields, and status methods are meaningless again — they're just not the main character anymore 💀
💜 getline_all 💜
$arrayref = $csv->getline_all ($fh);
$arrayref = $csv->getline_all ($fh, $offset);
$arrayref = $csv->getline_all ($fh, $offset, $length);returns a reference to a list of getline ($fh) results 🫶 in this call, keep_meta_info is disabled — just so you know.
if $offset is negative, same energy as splice: only the last abs ($offset) records of $fh get considered.
$offset and $length are expected to be integers. non-integer values are interpreted as integer without check — so like, no vibe check on your input, bestie 🙈
given a CSV file with 10 lines:
lines call
----- ---------------------------------------------------------
0..9 $csv->getline_all ($fh) # all
0..9 $csv->getline_all ($fh, 0) # all
8..9 $csv->getline_all ($fh, 8) # start at 8
- $csv->getline_all ($fh, 0, 0) # start at 0 first 0 rows
0..4 $csv->getline_all ($fh, 0, 5) # start at 0 first 5 rows
4..5 $csv->getline_all ($fh, 4, 2) # start at 4 first 2 rows
8..9 $csv->getline_all ($fh, -2) # last 2 rows
6..7 $csv->getline_all ($fh, -4, 2) # first 2 of last 4 rowsiconic behaviour honestly 👑
⭐ getline_hr ⭐
getline_hr and column_names are literally a duo — they work together so your rows come back as hashrefs 💖 you must call column_names first to declare your column names, okay?
$csv->column_names (qw( code name price description ));
$hr = $csv->getline_hr ($fh);
print "Price for $hr->{name} is $hr->{price} EUR\n";getline_hr will croak if you call it before column_names. rude? maybe. deserved? yeah 😭
also real talk: getline_hr creates a fresh hashref for every single row, so it's much slower than using bind_columns and getline together. but like, you still get the easy-to-use hashref inside the loop:
my @cols = @{$csv->getline ($fh)};
$csv->column_names (@cols);
while (my $row = $csv->getline_hr ($fh)) {
print $row->{price};
}which could easily be rewritten to the much faster:
my @cols = @{$csv->getline ($fh)};
my $row = {};
$csv->bind_columns (\@{$row}{@cols});
while ($csv->getline ($fh)) {
print $row->{price};
}your mileage may vary depending on the size of your data and the number of rows — fr fr. with perl-5.14.2, the comparison for a 100_000 line file with 14 columns:
Rate hashrefs getlines
hashrefs 1.00/s -- -76%
getlines 4.15/s 313% --the numbers did NOT come to play 🔥
🎀 getline_hr_all 🎀
$arrayref = $csv->getline_hr_all ($fh);
$arrayref = $csv->getline_hr_all ($fh, $offset);
$arrayref = $csv->getline_hr_all ($fh, $offset, $length);returns a reference to a list of getline_hr ($fh) results ✨ and in this call, keep_meta_info is disabled. same deal as before.
🌈 parse 🌈
$status = $csv->parse ($line);this one takes a CSV string apart into fields and hands you back success or failure 💅
failure happens if there's no argument at all, or if the CSV string you gave it is improperly formatted. on success, call fields to grab the decomposed fields. on failure, calling fields returns undefined data, and error_input can be called to retrieve the invalid argument 😭
you may use the types method for setting column types — see types' description below, bestie 👀
and listen: the $line argument is supposed to be a simple scalar. everything else is supposed to croak and set error 1500. no exceptions, no loopholes 🚫
🧚 fragment 🧚
this function tries to implement RFC7111 (URI Fragment Identifiers for the text/csv Media Type) — https://datatracker.ietf.org/doc/html/rfc7111 ✨
my $AoA = $csv->fragment ($fh, $spec);in specifications, * means the last item, and a dash (-) indicates a range. all indices are 1-based: the first row or column has index 1. selections can be combined with the semi-colon (;) 🎀
when you use this method together with column_names, the returned reference points to a list of hashes instead of a list of lists. but a disjointed cell-based combined selection might return rows with different numbers of columns, which makes using hashes unpredictable 😬
$csv->column_names ("Name", "Age");
my $AoH = $csv->fragment ($fh, "col=3;8");if the after_parse callback is active, it's also called on every line parsed and skipped before the fragment. every single one 💅
row
row=4
row=5-7
row=6-*
row=1-2;4;6-*col
col=2
col=1-3
col=4-*
col=1-2;4;7-*cell
in cell-based selection, the comma (,) is used to pair row and column 🫶
cell=4,1the range operator (-) using cells can define top-left and bottom-right cell location:
cell=3,1-4,6the * is only allowed in the second part of a pair — noted, bestie:
cell=3,2-*,2 # row 3 till end, only column 2
cell=3,2-3,* # column 2 till end, only row 3
cell=3,2-*,* # strip row 1 and 2, and column 1cells and cell ranges may be combined with ;, possibly resulting in rows with different numbers of columns:
cell=1,1-2,2;3,3-4,4;1,4;4,1disjointed selections will only return the selected cells. the cells that aren't specified will not be included in the returned set — not even as undef. literally not invited to the party 🙈 as an example, given a CSV like
11,12,13,...19
21,22,...28,29
: :
91,...97,98,99with cell=1,1-2,2;3,3-4,4;1,4;4,1 will return:
11,12,14
21,22
33,34
41,43,44overlapping cell-specs will return those cells only once, so cell=1,1-3,3;2,2-4,4;2,3;4,2 will return:
11,12,13
21,22,23,24
31,32,33,34
42,43,44RFC7111 <https://datatracker.ietf.org/doc/html/rfc7111> does not allow different types of specs to be combined (either row or col or cell). passing an invalid fragment specification will croak and set error 2013 💀
🍓 column_names 🍓
sets the keys that will be used in getline_hr calls. if no keys (column names) are passed, it returns the current setting as a list 🎀
column_names accepts a list of scalars (the column names) or a single array_ref, so you can totally pass the return value from getline too:
$csv->column_names ($csv->getline ($fh));okay but real talk: column_names does no checking on duplicates at all, which might lead to unexpected results 👀 undefined entries get replaced with the string \cAUNDEF\cA, so
$csv->column_names (undef, "", "name", "name");
$hr = $csv->getline_hr ($fh);will set $hr->{"\cAUNDEF\cA"} to the 1st field, $hr->{""} to the 2nd field, and $hr->{name} to the 4th field — discarding the 3rd field 😭 sorry babe, she's gone.
column_names croaks on invalid arguments. periodt.
👑 header 👑
this method does NOT work in perl-5.6.x 💀
it parses the CSV header and sets sep, column_names and encoding ✨
my @hdr = $csv->header ($fh);
$csv->header ($fh, { sep_set => [ ";", ",", "|", "\t" ] });
$csv->header ($fh, { detect_bom => 1, munge_column_names => "lc" });the first argument should be a file handle 🫶
this method resets some object properties, since it's supposed to be invoked only once per file or stream. it will leave the attributes column_names and bound_columns alone if setting column names is disabled. also, reading headers on previously processed objects might fail on perl-5.8.0 and older — so like, ancient, bestie 🦕
assuming the file opened for parsing has a header, and the header doesn't contain problematic characters like embedded newlines, it reads the first line from the open handle and then auto-detects whether the header separates the column names with a character from the allowed separator list 🔍
if any of the allowed separators matches, and none of the other allowed separators match, it sets sep to that separator for the current CSV instance, uses it to parse the first line, maps those to lowercase, and uses that to set the instance column_names:
my $csv = Text::CSV->new ({ binary => 1, auto_diag => 1 });
open my $fh, "<", "file.csv";
binmode $fh; # for Windows
$csv->header ($fh);
while (my $row = $csv->getline_hr ($fh)) {
...
}if the header is empty, contains more than one unique separator out of the allowed set, contains empty fields, or contains identical fields (after folding), it will croak with error 1010, 1011, 1012, or 1013 respectively — pick your fighter 😭
if the header contains embedded newlines, or isn't valid CSV in any other way, this method will croak and leave the parse error untouched.
a successful call to header will always set the sep of the $csv object. this behavior can not be disabled. it's giving non-negotiable 💅
return value
on error, this method will croak.
in list context, the headers will be returned whether they're used to set column_names or not 🎀
in scalar context, the instance itself is returned. note: the values as found in the header will effectively be lost if set_column_names is false 👀
Options
sep_set
$csv->header ($fh, { sep_set => [ ";", ",", "|", "\t" ] });the list of legal separators defaults to [ ";", "," ] and can be changed with this option. and since this is probably the most often used option, it can be passed on its own as an unnamed argument:
$csv->header ($fh, [ ";", ",", "|", "\t", "::", "\x{2063}" ]);multi-byte sequences are allowed — both multi-character and Unicode 🌈 see sep.
detect_bom
$csv->header ($fh, { detect_bom => 1 });The default vibe is: peek at the header line, and if it kicks off with a BOM, use that to set the encoding of $fh. Want to turn that off? Just pass a false value to detect_bom.
Encodings we can sniff from a BOM: UTF-8, UTF-16BE, UTF-16LE, UTF-32BE, and UTF-32LE. BOM itself also knows about UTF-1, UTF-EBCDIC, SCSU, BOCU-1, and GB-18030, but Encode doesn't (yet) 😭. UTF-7 is not supported, periodt.
If a supported BOM gets detected at the start of the stream, it's stashed in the object attribute ENCODING.
my $enc = $csv->{ENCODING};That encoding gets used with binmode on $fh.
If the handle was already opened in a (correct) encoding, this method will not touch the encoding — it checks the leading bytes of the first line. And if the stream starts with a decoded BOM (U+FEFF), {ENCODING} will be "" (empty) instead of the default undef.
munge_column_names
This one is your glow-up tool for column names — it lets you reshape them into whatever's most useful for your app. Default behavior? Every column name gets mapped to lower case.
$csv->header ($fh, { munge_column_names => "lc" });Here's the menu of values:
lc - lower case
uc - upper case
db - valid DB field names
none - do not change
\%hash - supply a mapping
\&cb - supply a callbackLower case
$csv->header ($fh, { munge_column_names => "lc" });Header goes all lower-case:
$_ = lc;Upper case
$csv->header ($fh, { munge_column_names => "uc" });Header goes ALL UPPER-CASE:
$_ = uc;Literal
$csv->header ($fh, { munge_column_names => "none" });Hash
$csv->header ($fh, { munge_column_names => { foo => "sombrero" });if a value does not exist, the original value is used unchanged 🫶
Database
$csv->header ($fh, { munge_column_names => "db" });- lower-case
- all sequences of non-word characters are replaced with an underscore
- all leading underscores are removed
$_ = lc (s/\W+/_/gr =~ s/^_+//r);Callback
$csv->header ($fh, { munge_column_names => sub { fc } });
$csv->header ($fh, { munge_column_names => sub { "column_".$col++ } });
$csv->header ($fh, { munge_column_names => sub { lc (s/\W+/_/gr) } });Because this callback is called inside a map, you can use $_ directly. iykyk 💅
set_column_names
$csv->header ($fh, { set_column_names => 1 });Default is to set the instance's column names using column_names if the method succeeds — so later getline_hr calls can hand you back a hash. You can force it off with a false value for this option.
And as we said in "return value" above, content is lost in scalar context. 😭
Validation
When you're receiving CSV files from external sources, this method is your bodyguard — it protects you from layout changes by restricting to known headers (and catching typos in the header fields). So iconic of it.
my %known = (
"record key" => "c_rec",
"rec id" => "c_rec",
"id_rec" => "c_rec",
"kode" => "code",
"code" => "code",
"vaule" => "value",
"value" => "value",
);
my $csv = Text::CSV->new ({ binary => 1, auto_diag => 1 });
open my $fh, "<", $source or die "$source: $!";
$csv->header ($fh, { munge_column_names => sub {
s/\s+$//;
s/^\s+//;
$known{lc $_} or die "Unknown column '$_' in $source";
}});
while (my $row = $csv->getline_hr ($fh)) {
say join "\t", $row->{c_rec}, $row->{code}, $row->{value};
}bind_columns
Takes a list of scalar references — these are the slots used for output with print, or the storage for fields fetched by getline. If you don't pass enough references to store the fetched fields in, getline will fail with error 3006. If you pass more than there are fields to return, the content of the remaining references is left untouched (they just vibe, unchanged). Under strict the two should match, otherwise getline will fail with error 2014.
$csv->bind_columns (\$code, \$name, \$price, \$description);
while ($csv->getline ($fh)) {
print "The price of a $name is \x{20ac} $price\n";
}Want to reset or clear all column binding? Call bind_columns with the single argument undef. Heads up: this also clears column names.
$csv->bind_columns (undef);And if you pass no arguments at all, bind_columns returns the list of current bindings — or undef if no binds are active.
Ngl this next bit matters: in parsing withbind_columns, the fields are set on the fly. That means if the third field of a row causes an error (or this row has just two fields where the previous row had more), the first two fields already have been assigned the values of the current row, while the rest of the fields will still hold the values of the previous row. Kind of a cursed mix 💀. If you want the parser to fail in these cases, use thestrictattribute.
eof
$eof = $csv->eof ();If parse or getline was used with an IO stream, this method returns true (1) if the last call hit end of file, otherwise it returns false (''). Super useful for telling the difference between a failure and end of file.
Note that if the parsing of the last line caused an error,eofis still true. Which means if you're not usingauto_diag, an idiom like
while (my $row = $csv->getline ($fh)) {
# ...
}
$csv->eof or $csv->error_diag;will not report the error. You'd have to change that to
while (my $row = $csv->getline ($fh)) {
# ...
}
+$csv->error_diag and $csv->error_diag;types
$csv->types (\@tref);This method forces that (all) columns are of a given type. Say you've got an integer column, two columns with doubles, and a string column — then you'd do
$csv->types ([Text::CSV::IV (),
Text::CSV::NV (),
Text::CSV::NV (),
Text::CSV::PV ()]);Column types are only used for decoding columns while parsing — in other words, by the parse and getline methods.
You can unset column types by doing
$csv->types (undef);or fetch the current type settings with
$types = $csv->types ();IV CSV_TYPE_IV Set field type to integer.
NV CSV_TYPE_NV Set field type to numeric/float.
PV CSV_TYPE_PV Set field type to string.
fields
@columns = $csv->fields ();This method returns the input to combine — or the resultant decomposed fields of a successful parse — whichever was called more recently.
Heads up though: the return value is undef after using getline, which does not fill the data structures returned by parse.
meta_info
@flags = $csv->meta_info ();This method returns the flags of the input to combine, or the flags of the resultant decomposed fields of parse, whichever was called more recently.
For each field, a meta_info field will hold flags that inform something about the field returned by the fields method, or passed to the combine method. The flags are bit-wise-or'd like this:
0x0001 CSV_FLAGS_IS_QUOTED The field was quoted.
0x0002 CSV_FLAGS_IS_BINARY The field was binary.
0x0004 CSV_FLAGS_ERROR_IN_FIELD The field was invalid.
Currently only used when allow_loose_quotes is active.
0x0010 CSV_FLAGS_IS_MISSING The field was missing.
See the is_*** methods below 👇
is_quoted
my $quoted = $csv->is_quoted ($column_idx);where $column_idx is the (zero-based) index of the column in the last result of parse.
This returns a true value if the data in the indicated column was enclosed in quote_char quotes. This might be important for fields where content ,20070108, is to be treated as a numeric value, and where ,"20070108", is explicitly marked as character string data.
This method is only valid when keep_meta_info is set to a true value.
is_binary
my $binary = $csv->is_binary ($column_idx);where $column_idx is the (zero-based) index of the column in the last result of parse.
Returns a true value if the data in the indicated column contained any byte in the range [\x00-\x08,\x10-\x1F,\x7F-\xFF].
This method is only valid when keep_meta_info is set to a true value.
is_missing
my $missing = $csv->is_missing ($column_idx);where $column_idx is the (zero-based) index of the column in the last result of getline_hr.
$csv->keep_meta_info (1);
while (my $hr = $csv->getline_hr ($fh)) {
$csv->is_missing (0) and next; # This was an empty line
}When using getline_hr, it's impossible to tell if the parsed fields are undef because they were not filled in the CSV stream or because they were not read at all, since all the fields defined by column_names are set in the hash-ref. If you still need to know if all fields in each row are provided, you should enable keep_meta_info so you can check the flags.
If keep_meta_info is false, is_missing will always return undef, regardless of $column_idx being valid or not. If this attribute is true it will return either 0 (the field is present) or 1 (the field is missing).
A special case is the empty line 🌸. If the line is completely empty — after dealing with the flags — this is still a valid CSV line: it's a record of just one single empty field. However, if keep_meta_info is set, invoking is_missing with index 0 will now return true.
status
$status = $csv->status ();Returns the status of the last invoked combine or parse call. Status is success (true: 1) or failure (false: undef or 0).
Note that since this only keeps track of the status of the above-mentioned methods, you're probably looking for error_diag instead 👀
error_input
$bad_argument = $csv->error_input ();Returns the erroneous argument (if it exists) of combine or parse, whichever was called more recently. If the last invocation was successful, error_input returns undef.
Depending on the type of error, it might also hold the data for the last error-input of getline.
error_diag
Text::CSV->error_diag ();
$csv->error_diag ();
$error_code = 0 + $csv->error_diag ();
$error_str = "" . $csv->error_diag ();
($cde, $str, $pos, $rec, $fld, $xs) = $csv->error_diag ();If (and only if) an error occurred, this function returns the diagnostics of that error. No error, no tea ☕ — nothing gets returned.
Okay so back to error_diag 💅 If you call it in void context, it prints the internal error code and the associated error message to STDERR — like, it's literally telling on itself 😭.
If you call it in list context, it returns the error code and the error message, in that order. If the last error was from parsing, the rest of the values returned are a best guess at the location within the line that was being parsed. Their values are 1-based. The position currently is index of the byte at which the parsing failed in the current record. It might change to be the index of the current character in a later release. The records is the index of the record parsed by the csv instance. The field number is the index of the field the parser thinks it is currently trying to parse. See examples/csv-check for how this can be used. If $xs is set, it is the line number in XS where the error was triggered (for debugging). "XS" will show in void context only when diag_verbose is set.
If you call it in scalar context, it returns the diagnostics in a single scalar, a-la $!. It will contain the error code in numeric context, and the diagnostics message in string context.
When called as a class method or a direct function call, the diagnostics are that of the last "new" call.
_cache_diag 🫣
Note: This is an internal function only, and output cannot be relied upon. Use at own risk.
If debugging beyond what "error_diag" is able to show, the internal cache can be shown with this function.
# Something failed ..
$csv->error_diag;
$csv->_cache_diag ();record_number 🔢
$recno = $csv->record_number ();Returns the records parsed by this csv instance. This value should be more accurate than $. when embedded newlines come in play. Records written by this instance are not counted.
SetDiag 🧹
$csv->SetDiag (0);Use to reset the diagnostics if you are dealing with errors.
ADDITIONAL METHODS 💖
backend— returns the backend module name called by Text::CSV."module"is an alias.is_xs— returns true value if Text::CSV uses an XS backend.is_pp— returns true value if Text::CSV uses a pure-Perl backend.
FUNCTIONS 🎀
This section is also taken from Text::CSV_XS.
csv 🦋
This function is not exported by default and should be explicitly requested:
use Text::CSV qw( csv );This is a high-level function that aims at simple (user) interfaces. This can be used to read/parse a "CSV" file or stream (the default behavior) or to produce a file or write to a stream (define the "out" attribute). It returns an array- or hash-reference on parsing (or "undef" on fail) or the numeric value of "error_diag" on writing. When this function fails you can get to the error using the class call to "error_diag"
my $aoa = csv (in => "test.csv") or
die Text::CSV->error_diag;Note that failure here is the inability to start the parser, like when the input does not exist or the arguments are unknown or conflicting. Run-time parsing errors will return a valid reference, which can be empty, but still contains all results up till the error. See "on_error".
This function takes the arguments as key-value pairs. This can be passed as a list or as an anonymous hash:
my $aoa = csv ( in => "test.csv", sep_char => ";");
my $aoh = csv ({ in => $fh, headers => "auto" });The arguments passed consist of two parts: the arguments to "csv" itself and the optional attributes to the "CSV" object used inside the function as enumerated and explained in "new".
If not overridden, the default option used for CSV is
auto_diag => 1
escape_null => 0
strict_eol => 1The option that is always set and cannot be altered is
binary => 1As this function will likely be used in one-liners, it allows "quote" to be abbreviated as "quo", and "escape_char" to be abbreviated as "esc" or "escape".
Alternative invocations:
my $aoa = Text::CSV::csv (in => "file.csv");
my $csv = Text::CSV->new ();
my $aoa = $csv->csv (in => "file.csv");In the latter case, the object attributes are used from the existing object and the attribute arguments in the function call are ignored:
my $csv = Text::CSV->new ({ sep_char => ";" });
my $aoh = $csv->csv (in => "file.csv", bom => 1);will parse using ";" as "sep_char", not ",".
in 📥 — where the data comes from
Used to specify the source. "in" can be a file name (e.g. "file.csv"), which will be opened for reading and closed when finished, a file handle (e.g. $fh or "FH"), a reference to a glob (e.g. "\*ARGV"), the glob itself (e.g. *STDIN), or a reference to a scalar (e.g. "\q{1,2,"csv"}").
When used with "out", "in" should be a reference to a CSV structure (AoA or AoH) or a CODE-ref that returns an array-reference or a hash-reference. The code-ref will be invoked with no arguments.
my $aoa = csv (in => "file.csv");
open my $fh, "<", "file.csv";
my $aoa = csv (in => $fh);
my $csv = [ [qw( Foo Bar )], [ 1, 2 ], [ 2, 3 ]];
my $err = csv (in => $csv, out => "file.csv");If called in void context without the "out" attribute, the resulting ref will be used as input to a subsequent call to csv:
csv (in => "file.csv", filter => { 2 => sub { length > 2 }})will be a shortcut to
csv (in => csv (in => "file.csv", filter => { 2 => sub { length > 2 }}))where, in the absence of the "out" attribute, this is a shortcut to
csv (in => csv (in => "file.csv", filter => { 2 => sub { length > 2 }}),
out => *STDOUT)out 📤 — where the data goes
csv (in => $aoa, out => "file.csv");
csv (in => $aoa, out => $fh);
csv (in => $aoa, out => STDOUT);
csv (in => $aoa, out => *STDOUT);
csv (in => $aoa, out => \*STDOUT);
csv (in => $aoa, out => \my $data);
csv (in => $aoa, out => undef);
csv (in => $aoa, out => \"skip");
csv (in => $fh, out => \@aoa);
csv (in => $fh, out => \@aoh, bom => 1);
csv (in => $fh, out => \%hsh, key => "key");
csv (in => $file, out => $file);
csv (in => $file, out => $fh);
csv (in => $fh, out => $file);
csv (in => $fh, out => $fh);In output mode, the default CSV options when producing CSV are
eol => "\r\n"The "fragment" attribute is ignored in output mode.
"out" can be a file name (e.g. "file.csv"), which will be opened for writing and closed when finished, a file handle (e.g. $fh or "FH"), a reference to a glob (e.g. "\*STDOUT"), the glob itself (e.g. *STDOUT), or a reference to a scalar (e.g. "\my $data").
csv (in => sub { $sth->fetch }, out => "dump.csv");
csv (in => sub { $sth->fetchrow_hashref }, out => "dump.csv",
headers => $sth->{NAME_lc});When a code-ref is used for "in", the output is generated per invocation, so no buffering is involved. This implies that there is no size restriction on the number of records. The "csv" function ends when the coderef returns a false value.
If "out" is set to a reference of the literal string "skip", the output will be suppressed completely, which might be useful in combination with a filter for side effects only.
my %cache;
csv (in => "dump.csv",
out => \"skip",
on_in => sub { $cache{$_[1][1]}++ });Currently, setting "out" to any false value ("undef", "", 0) will be equivalent to "\"skip\"".
If the "in" argument point to something to parse, and the "out" is set to a reference to an "ARRAY" or a "HASH", the output is appended to the data in the existing reference. The result of the parse should match what exists in the reference passed. This might come handy when you have to parse a set of files with similar content (like data stored per period) and you want to collect that into a single data structure:
my %hash;
csv (in => $_, out => \%hash, key => "id") for sort glob "foo-[0-9]*.csv";
my @list; # List of arrays
csv (in => $_, out => \@list) for sort glob "foo-[0-9]*.csv";
my @list; # List of hashes
csv (in => $_, out => \@list, bom => 1) for sort glob "foo-[0-9]*.csv";Streaming 🌊
If both "in" and "out" are files, file handles or globs, streaming is enforced by injecting an "after_parse" callback that immediately uses the "say ()" method of the same instance to output the result and then rejects the record.
If a "after_parse" was already passed as attribute, that will be included in the injected call. If "on_in" was passed and "after_parse" was not, it will be used instead. If both were passed, "on_in" is ignored.
The EOL of the first record of the "in" source is consistently used as EOL for all records in the "out" destination.
The "filter" attribute is not available.
All other attributes are shared for "in" and "out", so you cannot define different encodings for "in" and "out". You need to pass a $fh, where "binmode" was used to apply the encoding layers.
Note that this is work in progress and things might change.
encoding 🔤
If passed, it should be an encoding accepted by the :encoding() option to "open". There is no default value. This attribute does not work in perl 5.6.x. "encoding" can be abbreviated to "enc" for ease of use in command line invocations.
If "encoding" is set to the literal value "auto", the method "header" will be invoked on the opened stream to check if there is a BOM and set the encoding accordingly. This is equal to passing a true value in the option "detect_bom".
Encodings can be stacked, as supported by "binmode":
# Using PerlIO::via::gzip
csv (in => \@csv,
out => "test.csv:via.gz",
encoding => ":via(gzip):encoding(utf-8)",
);
$aoa = csv (in => "test.csv:via.gz", encoding => ":via(gzip)");
# Using PerlIO::gzip
csv (in => \@csv,
out => "test.csv:via.gz",
encoding => ":gzip:encoding(utf-8)",
);
$aoa = csv (in => "test.csv:gzip.gz", encoding => ":gzip");detect_bom 🔍
If "detect_bom" is given, the method "header" will be invoked on the opened stream to check if there is a BOM and set the encoding accordingly.
"detect_bom" can be abbreviated to "bom".
This is the same as setting "encoding" to "auto".
Note that as the method "header" is invoked, its default is to also set the headers.
headers 🏷️
If this attribute is not given, the default behavior is to produce an array of arrays.
If "headers" is supplied, it should be an anonymous list of column names, an anonymous hashref, a coderef, or a literal flag: "auto", "lc", "uc", or "skip".
skip 🙈
When "skip" is used, the header will not be included in the output.
my $aoa = csv (in => $fh, headers => "skip");"skip" is invalid/ignored in combinations with "detect_bom".
auto
okay so bestie, if you pass auto, the first line of your CSV source gets read as the list of field headers and used to produce an array of hashes. ✨
my $aoh = csv (in => $fh, headers => "auto");lc
If lc is used, the first line of the CSV source will be read as the list of field headers mapped to lower case and used to produce an array of hashes. This is a variation of auto. 🎀
my $aoh = csv (in => $fh, headers => "lc");uc
Same vibe but upper case: if uc is used, the first line of the CSV source will be read as the list of field headers mapped to upper case and used to produce an array of hashes. This is a variation of auto. 👑
my $aoh = csv (in => $fh, headers => "uc");CODE
If a coderef is used, the first line of the CSV source will be read as the list of mangled field headers in which each field is passed as the only argument to the coderef. This list is used to produce an array of hashes. 🧚
my $aoh = csv (in => $fh,
headers => sub { lc ($_[0]) =~ s/kode/code/gr });this example is a variation of using lc where all occurrences of kode are replaced with code.
ARRAY
If headers is an anonymous list, the entries in the list will be used as field names. The first line is considered data instead of headers. 😭
my $aoh = csv (in => $fh, headers => [qw( Foo Bar )]);
csv (in => $aoa, out => $fh, headers => [qw( code description price )]);HASH
If headers is a hash reference, this implies auto, but header fields that exist as key in the hashref will be replaced by the value for that key. Given a CSV file like 💅
post-kode,city,name,id number,fubble
1234AA,Duckstad,Donald,13,"X313DF"using
csv (headers => { "post-kode" => "pc", "id number" => "ID" }, ...will return an entry like
{ pc => "1234AA",
city => "Duckstad",
name => "Donald",
ID => "13",
fubble => "X313DF",
}See also "munge_column_names" and "set_column_names".
munge_column_names
If munge_column_names is set, the method "header" is invoked on the opened stream with all matching arguments to detect and set the headers. 🫶
"munge_column_names" can be abbreviated to "munge".
key
If passed, will default "headers" to "auto" and return a hashref instead of an array of hashes. Allowed values are simple scalars or array-references where the first element is the joiner and the rest are the fields to join to combine the key. 🔑
my $ref = csv (in => "test.csv", key => "code");
my $ref = csv (in => "test.csv", key => [ ":" => "code", "color" ]);with test.csv like
code,product,price,color
1,pc,850,gray
2,keyboard,12,white
3,mouse,5,blackthe first example will return
{ 1 => {
code => 1,
color => 'gray',
price => 850,
product => 'pc'
},
2 => {
code => 2,
color => 'white',
price => 12,
product => 'keyboard'
},
3 => {
code => 3,
color => 'black',
price => 5,
product => 'mouse'
}
}the second example will return
{ "1:gray" => {
code => 1,
color => 'gray',
price => 850,
product => 'pc'
},
"2:white" => {
code => 2,
color => 'white',
price => 12,
product => 'keyboard'
},
"3:black" => {
code => 3,
color => 'black',
price => 5,
product => 'mouse'
}
}The "key" attribute can be combined with "headers" for CSV data that has no header line, like
my $ref = csv (
in => "foo.csv",
headers => [qw( c_foo foo bar description stock )],
key => "c_foo",
);value
Used to create key-value hashes. Only allowed when "key" is valid. A "value" can be either a single column label or an anonymous list of column labels. In the first case, the value will be a simple scalar value, in the latter case, it will be a hashref. 💖
my $ref = csv (in => "test.csv", key => "code",
value => "price");
my $ref = csv (in => "test.csv", key => "code",
value => [ "product", "price" ]);
my $ref = csv (in => "test.csv", key => [ ":" => "code", "color" ],
value => "price");
my $ref = csv (in => "test.csv", key => [ ":" => "code", "color" ],
value => [ "product", "price" ]);with test.csv like
code,product,price,color
1,pc,850,gray
2,keyboard,12,white
3,mouse,5,blackthe first example will return
{ 1 => 850,
2 => 12,
3 => 5,
}the second example will return
{ 1 => {
price => 850,
product => 'pc'
},
2 => {
price => 12,
product => 'keyboard'
},
3 => {
price => 5,
product => 'mouse'
}
}the third example will return
{ "1:gray" => 850,
"2:white" => 12,
"3:black" => 5,
}the fourth example will return
{ "1:gray" => {
price => 850,
product => 'pc'
},
"2:white" => {
price => 12,
product => 'keyboard'
},
"3:black" => {
price => 5,
product => 'mouse'
}
}keep_headers
When using hashes, keep the column names into the arrayref passed, so all headers are available after the call in the original order. 🌸
my $aoh = csv (in => "file.csv", keep_headers => \my @hdr);This attribute can be abbreviated to "kh" or passed as "keep_column_names".
This attribute implies a default of "auto" for the "headers" attribute.
The headers can also be kept internally to keep stable header order:
csv (in => csv (in => "file.csv", kh => "internal"),
out => "new.csv",
kh => "internal");where "internal" can also be 1, "yes", or "true". This is similar to
my @h;
csv (in => csv (in => "file.csv", kh => \@h),
out => "new.csv",
headers => \@h);fragment
Only output the fragment as defined in the "fragment" method. This option is ignored when generating "CSV". See "out". 🦋
Combining all of them could give something like
use Text::CSV qw( csv );
my $aoh = csv (
in => "test.txt",
encoding => "utf-8",
headers => "auto",
sep_char => "|",
fragment => "row=3;6-9;15-*",
);
say $aoh->[15]{Foo};sep_set
If "sep_set" is set, the method "header" is invoked on the opened stream to detect and set "sep_char" with the given set. ✨
"sep_set" can be abbreviated to "seps". If neither "sep_set" nor "seps" is given, but "sep" is defined, "sep_set" defaults to [ sep ]. This is only supported for perl version 5.10 and up.
Note that as the "header" method is invoked, its default is to also set the headers.
set_column_names
If "set_column_names" is passed, the method "header" is invoked on the opened stream with all arguments meant for "header". 💅
If "set_column_names" is passed as a false value, the content of the first row is only preserved if the output is AoA:
With an input-file like
bAr,foo
1,2
3,4,5This call
my $aoa = csv (in => $file, set_column_names => 0);will result in
[[ "bar", "foo" ],
[ "1", "2" ],
[ "3", "4", "5" ]]and
my $aoa = csv (in => $file, set_column_names => 0, munge => "none");will result in
[[ "bAr", "foo" ],
[ "1", "2" ],
[ "3", "4", "5" ]]csv
The function "csv" can also be called as a method or with an existing Text::CSV object. This could help if the function is to be invoked a lot of times and the overhead of creating the object internally over and over again would be prevented by passing an existing instance. 🎀
my $csv = Text::CSV->new ({ binary => 1, auto_diag => 1 });
my $aoa = $csv->csv (in => $fh);
my $aoa = csv (in => $fh, csv => $csv);both act the same. Running this 20000 times on a 20 lines CSV file, showed a 53% speedup. 🔥
💬 Callbacks
Callbacks enable actions triggered from the inside of Text::CSV.
While most of what this enables can easily be done in an unrolled loop as described in the "SYNOPSIS" callbacks can be used to meet special demands or enhance the "csv" function.
error
$csv->callbacks (error => sub { $csv->SetDiag (0) });the "error" callback is invoked when an error occurs, but only when "auto_diag" is set to a true value. A callback is invoked with the values returned by "error_diag":
my ($c, $s);
sub ignore3006 {
my ($err, $msg, $pos, $recno, $fldno) = @_;
if ($err == 3006) {
# ignore this error
($c, $s) = (undef, undef);
Text::CSV->SetDiag (0);
}
# Any other error
return;
} # ignore3006
$csv->callbacks (error => \&ignore3006);
$csv->bind_columns (\$c, \$s);
while ($csv->getline ($fh)) {
# Error 3006 will not stop the loop
}after_parse
$csv->callbacks (after_parse => sub { push @{$_[1]}, "NEW" });
while (my $row = $csv->getline ($fh)) {
$row->[-1] eq "NEW";
}This callback is invoked after parsing with "getline" only if no error occurred. The callback is invoked with two arguments: the current "CSV" parser object and an array reference to the fields parsed.
The return code of the callback is ignored unless it is a reference to the string "skip", in which case the record will be skipped in "getline_all".
sub add_from_db {
my ($csv, $row) = @_;
$sth->execute ($row->[4]);
push @$row, $sth->fetchrow_array;
} # add_from_db
my $aoa = csv (in => "file.csv", callbacks => {
after_parse => \&add_from_db });This hook can be used for validation:
FAIL — Die if any of the records does not validate a rule:
okay so picking up right inside that after_parse example, the rest is:
after_parse => sub {
$_[1][4] =~ m/^[0-9]{4}\s?[A-Z]{2}$/ or
die "5th field does not have a valid Dutch zipcode";
}DEFAULT — invalid field? give it a fallback 💅
Replace invalid fields with a default value:
after_parse => sub { $_[1][2] =~ m/^\d+$/ or $_[1][2] = 0 }SKIP — bye-bye bad records 🫶
Skip records that have invalid fields — only applies to getline_all:
after_parse => sub { $_[1][0] =~ m/^\d+$/ or return \"skip"; }before_print — pre-print vibe check ✨
my $idx = 1;
$csv->callbacks (before_print => sub { $_[1][0] = $idx++ });
$csv->print (*STDOUT, [ 0, $_ ]) for @members;This callback gets invoked before printing with print only if no error occurred. It's called with two arguments: the current CSV parser object and an array reference to the fields passed.
The return code of the callback? Ignored, bestie.
sub max_4_fields {
my ($csv, $row) = @_;
@$row > 4 and splice @$row, 4;
} # max_4_fields
csv (in => csv (in => "file.csv"), out => *STDOUT,
callbacks => { before_print => \&max_4_fields });This callback is not active for combine.
Callbacks for csv () 🎀
The csv function lets you use some callbacks that don't integrate into XS internals — they're just here for the csv function vibes:
csv (in => "file.csv",
callbacks => {
filter => { 6 => sub { $_ > 15 } }, # first
after_parse => sub { say "AFTER PARSE"; }, # first
after_in => sub { say "AFTER IN"; }, # second
on_in => sub { say "ON IN"; }, # third
},
);
csv (in => $aoh,
out => "file.csv",
callbacks => {
on_in => sub { say "ON IN"; }, # first
before_out => sub { say "BEFORE OUT"; }, # second
before_print => sub { say "BEFORE PRINT"; }, # third
},
);filter — the record bouncer 💅
This callback filters records. It gets called just after a new record has been scanned. The callback accepts a:
hashref
The keys are the index to the row — the field name or field number, 1-based — and the values are subs that return true or false.
csv (in => "file.csv", filter => {
3 => sub { m/a/ }, # third field should contain an "a"
5 => sub { length > 4 }, # length of the 5th field minimal 5
});
csv (in => "file.csv", filter => { foo => sub { $_ > 4 }});If the keys to the filter hash contain any character that is not a digit, it will also implicitly set headers to "auto" unless headers was already passed as an argument. When headers are active and you're returning an array of hashes, the filter is not applicable to the header itself.
All sub results should match — as in AND.
The context of the callback sets $_ localized to the field indicated by the filter. The two arguments are as with all other callbacks, so you can see the other fields in the current row:
filter => { 3 => sub { $_ > 100 ? $_[1][1] =~ m/A/ : $_[1][6] =~ m/B/ }}If the context is set to return a list of hashes — headers is defined — the current record will also be available in the localized %_:
filter => { 3 => sub { $_ > 100 && $_{foo} =~ m/A/ && $_{bar} < 1000 }}If you use the filter to alter content by changing $_, make sure the sub returns true so the record doesn't get skipped:
filter => { 2 => sub { $_ = uc }}That will upper-case the second field, and then skip it if the resulting content evaluates to false. To always accept, end with truth:
filter => { 2 => sub { $_ = uc; 1 }}coderef
csv (in => "file.csv", filter => sub { $n++; 0; });If the argument to filter is a coderef, it's an alias or shortcut to a filter on column 0:
csv (filter => sub { $n++; 0 });is equal to
csv (filter => { 0 => sub { $n++; 0 });filter-name
csv (in => "file.csv", filter => "not_blank");
csv (in => "file.csv", filter => "not_empty");
csv (in => "file.csv", filter => "filled");These are predefined filters 🫶
Given a file like this — line numbers prefixed for doc purposes only:
1:1,2,3
2:
3:,
4:""
5:,,
6:, ,
7:"",
8:" "
9:4,5,6not_blank
Filter out the blank lines.
This filter is a shortcut for:
filter => { 0 => sub { @{$_[1]} > 1 or
defined $_[1][0] && $_[1][0] ne "" } }Due to the implementation, it's currently impossible to also filter lines that consist only of a quoted empty field. Those lines are also considered blank lines.
With the example above, lines 2 and 4 will be skipped.
not_empty
Filter out lines where all the fields are empty.
This filter is a shortcut for:
filter => { 0 => sub { grep { defined && $_ ne "" } @{$_[1]} } }A space is not regarded as being empty, so with the example data, lines 2, 3, 4, 5, and 7 are skipped.
filled
Filter out lines that have no visible data.
This filter is a shortcut for:
filter => { 0 => sub { grep { defined && m/\S/ } @{$_[1]} } }This filter rejects all lines that don't have at least one field that doesn't evaluate to the empty string.
With the example data, this filter would skip lines 2 through 8.
One could also use modules like Types::Standard:
use Types::Standard -types;
my $type = Tuple[Str, Str, Int, Bool, Optional[Num]];
my $check = $type->compiled_check;
# filter with compiled check and warnings
my $aoa = csv (
in => \$data,
filter => {
0 => sub {
my $ok = $check->($_[1]) or
warn $type->get_message ($_[1]), "\n";
return $ok;
},
},
);after_in — after the parse, before you get it 🦋
This callback is invoked for each record after all records have been parsed but before returning the reference to the caller. The hook is invoked with two arguments: the current CSV parser object and a reference to the record. The reference can be a reference to a HASH or a reference to an ARRAY, as determined by the arguments.
This callback can also be passed as an attribute without the callbacks wrapper.
before_out — glow-up before the print 🌸
This callback is invoked for each record before the record is printed. The hook is invoked with two arguments: the current CSV parser object and a reference to the record. The reference can be a reference to a HASH or a reference to an ARRAY, as determined by the arguments.
This callback can also be passed as an attribute without the callbacks wrapper.
This callback makes the row available in %_ if the row is a hashref. In that case %_ is writable and will change the original row.
on_in — the double-duty hook 👑
This callback acts exactly as the after_in or the before_out hooks.
This callback can also be passed as an attribute without the callbacks wrapper.
This callback makes the row available in %_ if the row is a hashref. In this case %_ is writable and will change the original row. So for example with:
my $aoh = csv (
in => \"foo\n1\n2\n",
headers => "auto",
on_in => sub { $_{bar} = 2; },
);$aoh will be:
[ { foo => 1,
bar => 2,
}
{ foo => 2,
bar => 2,
}
]on_error — catch the oops 💀
This callback acts exactly as the error hook.
my @err;
my $aoa = csv (in => $fh, on_error => sub { @err = @_ });is identical to
my $aoa = csv (in => $fh, callbacks => {
error => sub { @err = @_ },
});It can be used for ignoring errors as well as for just keeping the error in case of analysis after the csv () function has returned.
my @err;
my $aoa = csv (in => "bad.csv, on_error => sub { @err = @_ });
die Text::CSV->error_diag if @err or !$aoa;💅 DIAGNOSTICS 💅
okay so this whole section is also taken from Text::CSV_XS, bestie. 💖
Still under construction ...
If an error occurs, $csv->error_diag can be used to get information on the cause of the failure. Note that for speed reasons the internal value is never cleared on success, so using the value returned by error_diag in normal cases — when no error occurred — may cause unexpected results.
🚨 lowkey important: that stale-value thing is real. Don't trust error_diag as “no error” just because it returns something after a success. 😭
If the constructor failed, the cause can be found using error_diag as a class method, like Text::CSV->error_diag.
The $csv->error_diag method is automatically invoked upon error when the constructor was called with auto_diag set to 1 or 2, or when autodie is in effect. When set to 1, this will cause a warn with the error message, when set to 2, it will die. "2012 - EOF" is excluded from auto_diag reports.
Errors can be (individually) caught using the error callback.
The errors as described below are available. I have tried to make the error itself explanatory enough, but more descriptions will be added. For most of these errors, the first three capitals describe the error category:
INI— Initialization error or option conflict. 🛠️ECR— Carriage-Return related parse error. 🚗EOF— End-Of-File related parse error. 🏁EIQ— Parse error inside quotation. 🎀EIF— Parse error inside field. 🌸ECB— Combine error. 🧩EHR— HashRef parse related error. 🫶
And below should be the complete list of error codes that can be returned:
1001—"INI - sep_char is equal to quote_char or escape_char"— bestie, the separation character cannot be equal to the quotation character or to the escape character, because that would invalidate all parsing rules. 💀1002—"INI - allow_whitespace with escape_char or quote_char SP or TAB"— using theallow_whitespaceattribute when eitherquote_charorescape_charis equal toSPACEorTABis too ambiguous to allow. 🙈1003—"INI - \r or \n in main attr not allowed"— using defaulteolcharacters in eithersep_char,quote_char, orescape_charis not allowed. 🚫1004—"INI - callbacks should be undef or a hashref"— thecallbacksattribute only allows one to beundefor a hash reference. 🎀1005—"INI - EOL too long"— the value passed for EOL is exceeding its maximum length (16). 📏1006—"INI - SEP too long"— the value passed for SEP is exceeding its maximum length (16). 📏1007—"INI - QUOTE too long"— the value passed for QUOTE is exceeding its maximum length (16). 📏1008—"INI - SEP undefined"— the value passed for SEP should be defined and not empty. 🫠1010—"INI - the header is empty"— the header line parsed in theheaderis empty. 📭1011—"INI - the header contains more than one valid separator"— the header line parsed in theheadercontains more than one (unique) separator character out of the allowed set of separators. 🧐1012—"INI - the header contains an empty field"— the header line parsed in theheadercontains an empty field. 🕳️1013—"INI - the header contains nun-unique fields"— the header line parsed in theheadercontains at least two identical fields. (yes, “nun-unique” is exactly what the error says, iykyk 😭)1014—"INI - header called on undefined stream"— the header line cannot be parsed from an undefined source. 🫥1500—"PRM - Invalid/unsupported argument(s)"— function or method called with invalid argument(s) or parameter(s). 🚫1501—"PRM - The key attribute is passed as an unsupported type"— thekeyattribute is of an unsupported type. 🔑1502—"PRM - The value attribute is passed without the key attribute"— thevalueattribute is only allowed when a valid key is given. 🗝️1503—"PRM - The value attribute is passed as an unsupported type"— thevalueattribute is of an unsupported type. 💅2010—"ECR - QUO char inside quotes followed by CR not part of EOL"— wheneolhas been set to anything but the default, like"\r\t\n", and the"\r"is following the second (closing)quote_char, where the characters following the"\r"do not make up theeolsequence, this is an error. 🚗2011—"ECR - Characters after end of quoted field"— sequences like"1,foo,"bar"baz,22,1"are not allowed."bar"is a quoted field and after the closing double-quote, there should be either a new-line sequence or a separation character. 😬2012—"EOF - End of data in parsing input stream"— self-explaining. End-of-file while inside parsing a stream. Can happen only when reading from streams withgetline, as usingparseis done on strings that are not required to have a trailingeol. 🏁2013—"INI - Specification error for fragments RFC7111"— invalid specification for URI"fragment"specification. 🧩2014—"ENF - Inconsistent number of fields"— inconsistent number of fields under strict parsing. 😵💫2015—"ERW - Empty row"— an empty row was not allowed. 🫙2016—"EOL - Inconsistent EOL"— inconsistent End-Of-Line detected understrict_eolparsing. 📏2021—"EIQ - NL char inside quotes, binary off"— sequences like"1,"foo\nbar",22,1"are allowed only when thebinaryoption has been selected with the constructor. 🔥2022—"EIQ - CR char inside quotes, binary off"— sequences like"1,"foo\rbar",22,1"are allowed only when thebinaryoption has been selected with the constructor. 💀2023—"EIQ - QUO character not allowed"— sequences like""foo "bar" baz",qu"and"2023,",2008-04-05,"Foo, Bar",\n"will cause this error. 🙅♀️2024—"EIQ - EOF cannot be escaped, not even inside quotes"— the escape character is not allowed as last character in an input stream. 🚫2025—"EIQ - Loose unescaped escape"— an escape character should escape only characters that need escaping. Allowing the escape for other characters is possible with the attributeallow_loose_escapes. 🎀2026—"EIQ - Binary character inside quoted field, binary off"— binary characters are not allowed by default. Exceptions are fields that contain valid UTF-8, that will automatically be upgraded if the content is valid UTF-8. Setbinaryto1to accept binary data. 🌈2027—"EIQ - Quoted field not terminated"— when parsing a field that started with a quotation character, the field is expected to be closed with a quotation character. When the parsed line is exhausted before the quote is found, that field is not terminated. 😭2030—"EIF - NL char inside unquoted verbatim, binary off"2031—"EIF - CR char is first char of field, not part of EOL"2032—"EIF - CR char inside unquoted, not part of EOL"2034—"EIF - Loose unescaped quote"2035—"EIF - Escaped EOF in unquoted field"2036—"EIF - ESC error"2037—"EIF - Binary character in unquoted field, binary off"2110—"ECB - Binary character in Combine, binary off"2200—"EIO - print to IO failed. See errno"3001—"EHR - Unsupported syntax for column_names ()"3002—"EHR - getline_hr () called before column_names ()"3003—"EHR - bind_columns () and column_names () fields count mismatch"3004—"EHR - bind_columns () only accepts refs to scalars"3006—"EHR - bind_columns () did not pass enough refs for parsed fields"3007—"EHR - bind_columns needs refs to writable scalars"3008—"EHR - unexpected error in bound fields"3009—"EHR - print_hr () called before column_names ()"3010—"EHR - print_hr () called with invalid arguments"
👀 SEE ALSO 👀
Text::CSV_PPText::CSV_XSText::CSV::Encoded
🫶 AUTHORS and MAINTAINERS 🫶
- Alan Citterman
<alan[at]mfgrtl.com>wrote the original Perl module. Please don't send mail concerning Text::CSV to Alan, as he's not a present maintainer. 💌 - Jochen Wiedmann
<joe[at]ispsoft.de>rewrote the encoding and decoding in C by implementing a simple finite-state machine and added the variable quote, escape and separator characters, the binary mode and the print and getline methods. See ChangeLog releases0.10through0.23. 🛠️ - H.Merijn Brand
<h.m.brand[at]xs4all.nl>cleaned up the code, added the field flags methods, wrote the major part of the test suite, completed the documentation, fixed some RT bugs. See ChangeLog releases0.25and on. 🧹 - Makamaka Hannyaharamitu,
<makamaka[at]cpan.org>wroteText::CSV_PPwhich is the pure-Perl version ofText::CSV_XS. 🐪
New Text::CSV (since 0.99) is maintained by Makamaka, and Kenichi Ishigaki since 1.91. 👑
📜 COPYRIGHT AND LICENSE 📜
Text::CSV
Copyright (C) 1997 Alan Citterman. All rights reserved. Copyright (C) 2007-2015 Makamaka Hannyaharamitu. Copyright (C) 2017- Kenichi Ishigaki A large portion of the doc is taken from Text::CSV_XS. See below.
Text::CSV_PP:
Copyright (C) 2005-2015 Makamaka Hannyaharamitu. Copyright (C) 2017- Kenichi Ishigaki A large portion of the code/doc are also taken from Text::CSV_XS. See below.
Text:CSV_XS:
Copyright (C) 2007-2016 H.Merijn Brand for PROCURA B.V. Copyright (C) 1998-2001 Jochen Wiedmann. All rights reserved. Portions Copyright (C) 1997 Alan Citterman. All rights reserved.
This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.
okay bestie, that's the whole page 💖 this beauty comes from perl v5.40.2 and it's dated 2025-08-20 — slay, documented, and officially signed off by the source/version footer. 🎀✨
📦 where this page comes from
- epel 10: perl-Text-CSV 2.06-1.el10_2 · GPL-1.0-or-later OR Artistic-1.0-Perl
- 💖 girlified by deepseek-ai/DeepSeek-V4.1-Flash-1017 on : a language model's rewrite of the original, under its terms