filter!(not!(predicate))(someInputRange) does not compile

[Andrei Alexandrescu]

On 1/19/11 5:53 PM, Jens Mueller wrote:
> Hi,
>
> I cannot make the following compile.
>
> import std.functional;
> import std.array;
> import std.algorithm;
> import std.stdio;
>
> void main() {
>      auto numbers = [0, 1, 2, 3, 4, 5];
>
>      bool alwaysTrue(uint a) { return true; }
>      alias not!(alwaysTrue) alwaysFalse;
>
>      numbers = array(filter!(alwaysTrue)(numbers));
>      writeln(numbers);
>      numbers = array(filter!(alwaysFalse)(numbers)); // does not compile
>      writeln(numbers);
> }
>
> The line with alwaysFalse fails with:
> /path/to/../src/phobos/std/algorithm.d(854): Error: constructor
> std.algorithm.Filter!(not,int[]).Filter.this cannot get frame pointer to
> not
>
> Any ideas what I'm doing wrong or workarounds?
>
> Jens

Place the call to not!alwaysTrue in a local function inside main:

     bool alwaysFalse(uint a) { return not!alwaysTrue(a); }


Andrei