A new version of Regex-Core was added to project The Inbox:
http://source.squeak.org/inbox/Regex-Core-ct.69.mcz

==================== Summary ====================

Name: Regex-Core-ct.69
Author: ct
Time: 23 August 2021, 10:32:19.392748 pm
UUID: 03218e64-f6d8-7349-84be-00f61d947856
Ancestors: Regex-Core-mt.61

Adds String >> #escapeRegex to escape special characters in a string before composing it into another regex.

Usage:

	':-)' matchesRegex: ':-)' escapeRegex

Supersedes Regex-Core-ct.61. Reuploaded to optimize #escapeString:. Thanks to Levente (ul) for the detailed instructions!

=============== Diff against Regex-Core-mt.61 ===============

Item was added:
+ ----- Method: RxParser class>>escapeString: (in category 'utilities') -----
+ escapeString: aString
+ 	"Answer a copy of aString which does not contain any unescaped characters. This is the inverse function of String >> #matchesRegex:.
+ 	NB: Basically, we could simply escape every single character in the string, but this would not produce human-readable outputs."
+ 
+ 	| special lastIndex nextIndex |
+ 	special := self specialCharacters.
+ 	nextIndex := aString indexOfAnyOf: special startingAt: (lastIndex := 1) ifAbsent: [^ aString].
+ 	^ String new: aString size * 11 // 10 "+10%" streamContents: [:stream |
+ 		[stream
+ 			next: nextIndex - lastIndex putAll: aString startingAt: lastIndex;
+ 			nextPut: $\;
+ 			nextPut: (aString at: nextIndex)]
+ 				doWhileTrue: [(nextIndex := aString indexOfAnyOf: special startingAt: (lastIndex := nextIndex + 1)) > 0].
+ 		stream next: aString size - lastIndex + 1 putAll: aString startingAt: lastIndex]!

Item was added:
+ ----- Method: RxParser class>>specialCharacters (in category 'utilities') -----
+ specialCharacters
+ 
+ 	^ '()[]*+?{}.^$:\'!

Item was added:
+ ----- Method: String>>escapeRegex (in category '*Regex-Core') -----
+ escapeRegex
+ 
+ 	^ RxParser escapeString: self!