On Monday, 2 June 2014 at 06:56:54 UTC, captaindet wrote:
hi,
i stumbled upon something weird - it looks like a bug to me but
maybe it is a "feature" that is unclear to me.
so i know i can declare function and delegate pointers at
module level.
for function pointers, i can initialize with a lambda.
BUT for delegates i get an error - see below
i found out that using module static this(){...} provides a
workaround, but why is this necessary?
also, if there is a good reason after all then the error
message should make more sense.
/det
ps: i know there is a shorthand syntax for this.
----
module demo;
int function(int) fn = function int(int){ return 42; };
// ok
int delegate(int) dg = delegate int(int){ return 666; };
// demo.d(6): Error: non-constant nested delegate literal
expression __dgliteral6
void main(){}
This doesn't work, because a delegate needs a context it can
capture, which is available only inside of a function.
The workaround is either, as Mr Smith suggests, to use a static
constructor, or you can use std.functional.toDelegate()
(probably, didn't test).
