Return value of String.match has an index property

[binil]

"x".match(/.*/).index

fails to compile. The String.match function is declared as:

interface String {
    match(regexp: RegExp): string[];
}

Instead, String.match(_: RegExp) should probably return an interface which is a string[] but has an extra index property.

There's also an extra input property on the array with the value of the this string.

"abcabc".match(/b/).input === "abcabc"

Originally filed at: http://typescript.codeplex.com/workitem/2175

[RyanCavanaugh]

This is only true when the g flag is not specified ('foo'.match(/o/g).index === undefined); perhaps we should make you cast this since we can't tell whether or not that's the case?

[danquirk]

Yeah, that's why we hadn't done it before. We don't have a great way to model this kind of API.

[sophiajt]

We should add both .index and .input as ? properties of return of match. To do so, we need a type that works as both a string[] and contains those additional properties.