Char.Ascii(3)

💖 NAME 💖

Char.Ascii — ASCII character set support.

okay so this is the OCaml library page for Char.Ascii, bestie, and it's literally all about ASCII character set support. tiny module, main character energy 💅

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🧚 MODULE 🧚

Module Char.Ascii

🌈 DOCUMENTATION 🌈

Module Ascii : sig end

ASCII character set support.

These functions give meaning to the integers [ 0x00 ; 0x7F ] of the ASCII character set.

Since the UTF-8 encoding of Unicode has the same encoding and character semantics (U+0000 to U+001F) for these bytes, the functions can be safely used on elements of UTF-8 encoded string and bytes values. However, the functions only deal with ASCII-related matters. For example, the notion of Unicode whitespace is much larger than the ASCII whitespace determined by Char.Ascii.is_white.

Since 5.4 ✨

🎀 Characters 🎀

• val min : char — min is '\x00'.
• val max : char — max is '\x7F'.

🌸 Predicates 🌸

• val is_valid : char -> bool — is_valid c is true if and only if c is an ASCII character, that is a byte in the range [ Char.Ascii.min ; Char.Ascii.max ].
• val is_upper : char -> bool — is_upper c is true if and only if c is an ASCII uppercase letter 'A' to 'Z', that is a byte in the range [ 0x41 ; 0x5A ].
• val is_lower : char -> bool — is_lower c is true if and only if c is an ASCII lowercase letter 'a' to 'z', that is a byte in the range [ 0x61 ; 0x7A ].
• val is_letter : char -> bool — is_letter c is Char.Ascii.is_lower c || Char.Ascii.is_upper c. that's the whole rule, no cap.
• val is_alphanum : char -> bool — is_alphanum c is Char.Ascii.is_letter c || Char.Ascii.is_digit c.
• val is_white : char -> bool — is_white c is true if and only if c is an ASCII white space character, and that means one of: tab '\t' (0x09), newline '\n' (0x0A), vertical tab (0x0B), form feed (0x0C), carriage return '\r' (0x0D) or space ' ' (0x20). iconic little list.
• val is_blank : char -> bool — is_blank c is true if and only if c is an ASCII blank character, that is either space ' ' (0x20) or tab '\t' (0x09).
• val is_graphic : char -> bool — is_graphic c is true if and only if c is an ASCII graphic character, that is a byte in the range [ 0x21 ; 0x7E ].
• val is_print : char -> bool — is_print c is Char.Ascii.is_graphic c || c = ' '.
• val is_control : char -> bool — is_control c is true if and only if c is an ASCII control character, that is a byte in the range [ 0x00 ; 0x1F ] or 0x7F.

🍓 Decimal digits 🍓

• val is_digit : char -> bool — is_digit c is true if and only if c is an ASCII decimal digit '0' to '9', that is a byte in the range [ 0x30 ; 0x39 ].
• val digit_to_int : char -> int — digit_to_int c is the numerical value of a digit that satisfies Char.Ascii.is_digit. Raises Invalid_argument if Char.Ascii.is_digit c is false. so don't feed it nonsense, bestie 😭
• val digit_of_int : int -> char — digit_of_int n is an ASCII decimal digit for the decimal value abs (n mod 10).

🦋 Hexadecimal digits 🦋

• val is_hex_digit : char -> bool — is_hex_digit c is true if and only if c is an ASCII hexadecimal digit '0' to '9', 'a' to 'f' or 'A' to 'F', that is a byte in one of the ranges [ 0x30 ; 0x39 ], [ 0x41 ; 0x46 ], [ 0x61 ; 0x66 ].
• val hex_digit_to_int : char -> int — hex_digit_to_int c is the numerical value of a digit that satisfies Char.Ascii.is_hex_digit. Raises Invalid_argument if Char.Ascii.is_hex_digit c is false.
• val lower_hex_digit_of_int : int -> char — lower_hex_digit_of_int n is a lowercase ASCII hexadecimal digit for the hexadecimal value abs (n mod 16).
• val upper_hex_digit_of_int : int -> char — upper_hex_digit_of_int n is an uppercase ASCII hexadecimal digit for the hexadecimal value abs (n mod 16).

👑 Casing transforms 👑

• val uppercase : char -> char — uppercase c is c with ASCII characters 'a' to 'z' respectively mapped to uppercase characters 'A' to 'Z'. Other characters are left untouched.
• val lowercase : char -> char — lowercase c is c with ASCII characters 'A' to 'Z' respectively mapped to lowercase characters 'a' to 'z'. Other characters are left untouched.

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