Sent from my iPad
> On Jan 23, 2017, at 7:49 AM, Joshua Alvarado <alvaradojosh...@gmail.com>
> wrote:
>
> The strings proposal is a warm welcome to the Swift Language and I believe
> many developers are happy to see Strings become a priority. String processing
> may be one of the most common tasks for a developer day to day. That being
> said one thing in the proposal I believe is not correct is the leaving out
> regular expressions.
>
>> "Addressing regular expressions is out of scope for this proposal."
We shouldn't have said "this proposal," because it's a manifesto, not a
proposal. Addressing Regexps in Swift proper is out of scope for Swift 4,
because there's simply no time to design and add the necessary language
features.
> Working with regular expressions in both Objective-c and Swift is a real
> pain. I don't believe that because NSRegularExpression exists is a good
> enough reason to leave it out of Swift 4 string improvements.
> NSRegularExpression is NOT easily retrofitted to strings.
It should be easy to retrofit it to the pattern matching system so
NSRegularExpression it works smoothly in Swift, but NSRegularExpression is
outside the standard library so this is something to take up with the
Foundation maintainers.
> Perl, ruby, javascript and many more programming languages have native easy
> to use regular expression functionality built in.
>
> Examples:
> Ruby:
> /hey/ =~ 'hey what's up'
> /world/.match('hello world')
>
> Javascript:
> 'javascript regex'.search(/regex/)
> 'hello replace'.replace(/replace/, 'world')
>
> Perl
> $statement = "The quick brown fox";
>
> if ($statement = /quick/) {
> print "this is what's up\n";
> }
>
> Now let's look at NSRegularExpression...
>
> Swift:
> do {
> let pattern = "\\w" // escape everything
> let regex = NSRegularExpression(pattern, options)
> let results = regex.matches(in: str, options: .reportCompletion, range:
> NSRange(location: 0, length: str.characters.distance(from: str.startIndex,
> to: str.endIndex)))
>
> results.forEach {
> print($0) // why is this a NSTextCheckResult?!
> }
> } catch {
> // welp out of luck
> }
>
> Yes I'm fully aware of the method:
>
> str.replaceOccurences(of: "pattern" with: "something" options:
> .regularExpression, range: nil)
>
> but it is just not enough for what is needed. Also, it is confusing to have a
> replace regex method separate from NSRegularExpression. It was not easy to
> find.
>
> Taken from NSHipster:
>> Happily, on one thing we can all agree. In NSRegularExpression, Cocoa has
>> the most long-winded and byzantine regular expression interface you’re ever
>> likely to come across.
>
> There is no way to achieve the goal of being better at string processing than
> Perl without regular expressions being addressed. It just should not be
> ignored.
It's not being ignored. We are laying the crucial foundation required for both
Regexp support and more general pattern-matching. We do, however, have to do
some things later, and a full treatment of regexps is one such thing.
-Dave_______________________________________________
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