toDelegate() for D1
Stewart Gordon
smjg_1998 at yahoo.com
Fri Jan 14 11:00:20 PST 2011
On 13/01/2011 17:14, %u wrote:
> == Quote from Simen kjaeraas (simen.kjaras at gmail.com)'s article
>> %u<e at ee.com> wrote:
>>> I only need something to make a void deleg() from a void func().
>> This works for me:
>> ReturnType!( F ) delegate( ParameterTypeTuple!( F ) ) toDelegate( F )( F
>> fn ) {
>> return ( ParameterTypeTuple!( F ) args ){ return fn( args ); };
>> }
>
> What am I doing wrong. I can't call the delegate twice with anything in between.
Every delegate needs a context pointer. If the function is defined
within a function, that context pointer points to the stack frame of the
function that defined it. And in this case it uses something from that
very stack frame: the parameter fn.
ISTM it works straight after you've created it only because the stack
frame of toDelegate has not yet been overwritten. However, I'm still
puzzled, because the process of calling the delegate ought to itself
overwrite the stack frame.
You want this:
http://pr.stewartsplace.org.uk/d/sutil/
Stewart.
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