Re: How do i use std.functional.binaryFun?
On Tuesday, 9 December 2014 at 01:17:47 UTC, anonymous wrote: Looks like a compiler bug. Filed: https://issues.dlang.org/show_bug.cgi?id=13843
How do i use std.functional.binaryFun?
How do i successfully use std.functional.binaryFun in the
following example?
import std.stdio;
import std.functional;
class Foo(T, alias greater = a b) if
(is(typeof(binaryFun!(greater)(T.init, T.init)) == bool))
{
private alias compare = binaryFun!(greater);
public this()
{
writefln(%s, this.compare(2, 1));
}
}
void main(string[] args)
{
auto foo = new Foo!(int, a b); // Works
auto bar = new Foo!(int, delegate(int a, int b){ return a b;
}); // Linker error.
}
The first instantiation works when using a string but I get a
linker error when i try and use a delegate as the compare
function. Why is this? and what do i need to do to correct this?
Re: How do i use std.functional.binaryFun?
On Monday, 8 December 2014 at 20:08:35 UTC, Gary Willoughby wrote:
import std.stdio;
import std.functional;
class Foo(T, alias greater = a b) if
(is(typeof(binaryFun!(greater)(T.init, T.init)) == bool))
{
private alias compare = binaryFun!(greater);
public this()
{
writefln(%s, this.compare(2, 1));
}
}
void main(string[] args)
{
auto foo = new Foo!(int, a b); // Works
auto bar = new Foo!(int, delegate(int a, int b){ return a b;
}); // Linker error.
}
Looks like a compiler bug.
A call without this. works. When you insert a call without
this., other calls with this. work, too.
A delegate with an implicit parameter type works: `Foo!(int,
delegate(int a, /*!*/ b){ return a b;})`.
