# SE-0354: Regex Literals

**URL:** <https://forums.swift.org/t/se-0354-regex-literals/57037>\
**Category:** Proposal Reviews\
**Created:** [April 28, 2022, 2:22pm UTC](https://forums.swift.org/t/se-0354-regex-literals/57037 "2022-04-28T14:22:27Z")\
**Posts on this page:** 1\
**Showing post:** 12

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**Author:** ![YOCKOW](https://sea2.discourse-cdn.com/swift/user_avatar/forums.swift.org/yockow/32/20636_2.png) [@YOCKOW](https://forums.swift.org/u/YOCKOW)\
**Post date:** [April 28, 2022, 11:53pm UTC](https://forums.swift.org/t/se-0354-regex-literals/57037/12 "2022-04-28T23:53:21Z")

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Sorry, but let me claim it again.

> [@\[Pitch #2\] Regex Literals](https://forums.swift.org/t/pitch-2-regex-literals/56736/54):
>
> General remarks about bare `/.../` :
> 
> I guess the reason why some people support `/.../` is because _"we have seen it in other languages"_ .  
> However, we have to remember that Swift is different from other languages in many senses.
> 
> First, (as mentioned repeatedly in this thread,) we can define prefix/infix/postfix operators containing `/` .  
> Authors simply think it is enough to change the syntax rule of Swift, but the fact that certain number of projects will be broken [has come to light](https://forums.swift.org/t/pitch-2-regex-literals/56736/25).
> 
> Second, regex in Swift may differ from ones in other languages.  
> Although this is out of scope of this pitch, it is related still.
> 
> > [@Declarative String Processing Overview](https://forums.swift.org/t/declarative-string-processing-overview/52459/95):
> >
> > When applied with grapheme-cluster semantics (the default if applied to `String` ), it would match grapheme-cluster by grapheme-cluster and comparison obeys canonical equivalence. There are some features that might not be supported, e.g. generalizing some scalar properties to grapheme clusters. Resulting indices would be grapheme-cluster aligned.
> 
> Such feature would confuse some folks especially from other languages.  
> Let me quote my opinion from pitch#1 thread:
> 
> > [@\[Pitch\] Regular Expression Literals](https://forums.swift.org/t/pitch-regular-expression-literals/52820/64):
> >
> > My thoughts are
> > 
> > > - If Swift adopts similar literals with e.g. Perl, semantics should be similar with Perl.
> > > - If Swift adopts different semantics from e.g. Perl, literals should be different from Perl.
> > > 
> > > That would be called perceived affordance.
> 
> Lastly, Swift has sublime philosophy (I hope).  
> I agree that `/.../` is simple and easy to write.  
> However, to be simple is not enough to be good in Swift.  
> I want to quote Mr. Lattner's utterance:
> 
> > [@\`if let\` shorthand](https://forums.swift.org/t/if-let-shorthand/54230/130):
> >
> > The goal of Swift language design isn't to minimize number of characters in code, it is to find a balance between "expressivity", and "readability". Readability isn't just "what does this line of code do" it is a deeper "what is the lifecycle of maintaining and evolving a codebase, particularly when it is worked on by multiple people, or the project spans years of development".
> 
> `/.../` will certainly break Swift.  
> `/.../` is not Swift's.  
> Does Swift have to borrow the syntax from others to break itself?  
> Will we get more benefit from `/.../` than loss from it?  
> _Think different._

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