Added a new popGrapheme function to std.uni

[dukc]

Since it's Hackathon today, even if I'm not there I decided to do something in similar spirit.

@atilaneves new symbol canditate for phobos, meaning it needs your approval!

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[dukc]

ping @atilaneves

[atilaneves]

This side note sounds like it should be its own PR.

[dukc]

It is. I felt an added @nogc compability to an existing funtion alone wasn't worth a changelog entry so didn't add one in that PR. But since I'm writing here that graphemeStride is @nogc anyway, which until very recently wasn't the case, I feel it's useful to mention it. As in: "this note applies only with the latest compiler/Phobos".

[atilaneves]

I don't know how useful this is so I would like someone that knows/cares about unicode more than me opines. Not sure who. @rikkimax ?

[rikkimax]

I don't know how useful this is so I would like someone that knows/cares about unicode more than me opines. Not sure who. @rikkimax ?

It allows you to get the grapheme length extracted, so you can slice and dice your string without allocation.

Kinda like graphemeStride except it pops it from the input like parse does.

It is one of those things that if a unicode library is being used you'll end up having a hundred variations of. I see nothing wrong with wanting functions like this.