Check/Compare a value using "in"

[Adam D. Ruppe]

On Saturday, 3 November 2012 at 01:42:21 UTC, MattCoder wrote:
> I need to check if some value exists in a list (Array).

Try something like this:

import std.algorithm;

if(['+', '-'].canFind(ch)) {
    // it was there
}

You could also write a little function to reverse the order

bool inside(T)(T t, T[] arr) {
	return arr.canFind(t);
}


void main() {
	assert('+'.inside(['+', '-']));
}


The in operator doesn't work on built in arrays because the 
language designers worry about matching the speed and semantics 
you expect from in when used on associative arrays.

But the functions are easy to use too so IMO in array isn't 
needed anyway.