count until predicate returns false

Simen Kjaeraas simen.kjaras at
Mon Aug 15 12:58:27 PDT 2011

On Mon, 15 Aug 2011 21:53:11 +0200, Andrej Mitrovic  
<andrej.mitrovich at> wrote:

> This will print the count of whitespace chars in a line:
> writeln(count!isWhite(line));
> What I need is the count of whitspace chars until the first
> non-whitespace char is found, essentially I need a "countWhile"
> template:
> writeln(countWhile!isWhite(line));
> Can I do this with existing templates somehow?

There is std.algorithm.countUntil, which does what's basically
the opposite. Just negate your predicate, and presto's your uncle.


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