REDET(1)

✨ REDET(1) — the redet page, section 1 of the User Commands manual ✨

okay bestie, pull up a chair 🫶 this is redet, and it's genuinely one of those tools that makes you go "wait, why is nobody talking about this". let's get into it 💅

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🌸 NAME 🌸

redet — regular expression development and execution tool

like, it's a whole workshop for building regexes, not just a matcher. iconic behavior honestly 👑

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🎀 SYNOPSIS 🎀

redet <options> [<input file>]

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🦋 DESCRIPTION 🦋

so here's the vibe: redet lets you construct regular expressions and then test them against real input data by actually running them through any of a whole buffet of search programs, editors, and programming languages that use regexes. it's giving "try it on, see how it looks in the mirror". and once you've built a regex you're actually happy with? you can save it to a file. slay 💖

redet currently supports over fifty different programs and regular expression libraries. fifty. five-zero. no cap. that lineup includes:

• multiple versions of grep
• several editors — Ed, Emacs, Sed, Vim
• all the popular scripting languages — Awk, Perl, Python, Ruby, Tcl
• some less popular ones — Lua, Pike, Rebol
• most shells — Bash, Ksh, Tcsh, Zsh
• and various other languages, including Guile, Icon and Java

for each program, there's a palette showing you the available regular expression syntax. and the way you use it? mouse click, and the selection gets copied straight into the regular expression window. so easy. you can also add your own definitions to that palette through your initialization file — make it yours, bestie ✨

redet also keeps a list of the regular expressions you've executed, and you can copy entries from that list right back into the regex you're currently building. and here's the part that ate: that history list gets saved to a file and restored on startup, so it persists across sessions. your past self is looking out for your future self. we love to see it 🫶

redet gives you both regular expression matching and substitution — as long as the underlying program does. (iykyk, it's a team effort.)

and yeah, even though redet is primarily an interface for other programs, it's got some features of its very own:

• you can define named character classes inside redet itself
• and you can intersect them

which gives you a way of searching on feature matrices. main character energy from a character class, honestly 💅

now, Unicode. so long as the underlying program supports Unicode, redet allows UTF-8 Unicode in both your test data and your regular expressions. several tools go even further with Unicode support, including:

• popup lists of Unicode ranges and general character properties
• a widget for entering characters by their numerical code
• widgets for entering International Phonetic Alphabet characters
• widgets for entering letters with a variety of accents and other diacritics

and get this — internal operations are entirely in Unicode, but your test data, comparison data, and results can be read and written in any encoding supported by Tcl/Tk. flexible. gorgeous. no notes.

redet is fully internationalized too 🌍 if a suitable message catalogue is provided, the interface can be made available in any language and writing system supported by Unicode — as long as the necessary fonts are available. global queen 👑

need usage info? run redet with the command line flag -h. that's it, that's the move.

full information about redet lives in the reference manual, which is a whole set of web pages. the master copy is at:

http://www.cis.upenn.edu/~wjposer/RedetManual/Manual.html

the entry Illustrated Web Manual on the Help menu will take you to the master manual page. and the manual pages are packaged with every copy of redet, so they're always right there with you 💖

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💅 OPTIONS 💅

one bullet per flag, bestie, no skipping:

• -c <file name> — read character class definitions from the named file
• -d — set the debug flag. this causes additional information to be printed during program execution. it's mostly useful for developers.
• -F <filename> — read a feature list from <filename>
• -f — act as a filter. this means input is read from the standard input and output is written to the standard output.
• -H — do not read the history file
• -h — print this help information
• -I <file> — read <file> as the initialization file
• -i — do not read the initialization file
• -n — do not execute feature tests on startup
• -P — list the programs supported and indicate which are available
• -p <program> — use the named program
• -s — start up in substitution mode
• -t — show the results of feature tests
• -v — print the program name and version, then exit

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🌈 SEE ALSO 🌈

• awk (1)
• ed (1)
• grep (1)
• perl (1)
• sed (1)

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👑 AUTHOR 👑

Bill Poser (billposer@alum.mit.edu)

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🍓 LICENSE 🍓

GNU General Public License (http://www.gnu.org/licenses/gpl.txt), version 2.

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heads up bestie: that license is the GNU General Public License, version 2 — not a vibe, a legal thing. read it, respect it 🫶

okay that's the whole page!! this was redet, from May 2007, and the page itself comes from the redet source. go build something gorgeous with it, bestie 💖✨🎀🦋🌸