JavaScript Pattern Matching Proposal

Re:JavaScript Pattern Matching Proposal by codedokode on Wednesday April 25, 2018 @11:46AM (#16922636)

It could look like this:

    var x = match (response) {
        case { status:200 }: true;
        case { status: 404 }: false;
        case Number: 0;
        case SomeClass: 1;
        default: -1;
    };

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Re:JavaScript Pattern Matching Proposal by ThurmaUman on Wednesday April 25, 2018 @12:24PM (#16923111)

so make switch first class?

    var x = (switch(true){
        case response === { status: 200 }:
            return true;
        case response === { status: 404 }:
            return false;
        case response === Number:
            return 0;
        case response === SomeClass: 
            return 1;
        default:
            return -1;
    });

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Re:JavaScript Pattern Matching Proposal by masklinn on Wednesday April 25, 2018 @12:55PM (#16923498)

> so make switch first class?

No. That would make the actual switch statement a value, rather than make switches expressions. And your version is completely different as you make cases into guards rather than labels or patterns.

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Re:JavaScript Pattern Matching Proposal by kbp on Thursday April 26, 2018 @01:42AM (#16929107)

This would introduce a weird inconsistency with cases for match and cases for switch regarding fallthrough, though. If it's going to look like cases in a switch statement, it should act like them, for better or worse.

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