On 12/24/2016 08:36 AM, aliak wrote:
"Cannot apply `()' to a value of type `Command!(__lambda1, int)". I
think it's failing when it checks for "!isFunctionPointer!A &&
!isDelegate!A".
Storing delegates is a workaround. Three notes in the code:
// (1) Added imports
import std.variant;
import std.stdio;
import std.algorithm;
struct Command(alias fun, Args...) {
Args args;
this(Args args) {
this.args = args; /* (2) args = args was a common mistake.
* dmd, please warn about this one.
* (I think there is a bug about that.)
*/
}
auto opCall() {
writefln("opCall called for %s", args);
return fun(args);
}
}
auto command(alias fun, Args...)(Args args) {
auto c = Command!(fun, Args)(args);
writefln("Created %s", c);
// (3) Workaround: Storing delegates, not Command instances.
return () => c();
}
void main() {
auto commands = variantArray(
command!(a => a + 1)(1),
command!(a => a + 2)(1),
command!(a => a + 3)(1),
);
commands.each!(a => a());
typeid(commands[0]).writeln; // std.variant.VariantN!32LU.VariantN
auto cmd = command!(a => a + 1)(1);
typeid(cmd).writeln; // scratchpad.main.Command!(__lambda4,
int).Command
}
Alid
