November 16, 2012 Delegate bug? | ||||
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Hi. I'm writing an Event class, and have the following code (important line highlighted): class Event(TEventArgs : EventArgs = EventArgs) { alias void delegate(Object, TEventArgs) THandlerFn; SList!(THandlerFn) handlers; Event opOpAssign(string op)(void delegate() handler) { static if (op == "+") { >>> handlers.insert( (Object o, EventArgs e) { handler(); } ); return this; } else static assert(0, "Operator "~op~" not implemented"); } } Usage: Event!EventArgs Close; Close += { ... some delegate code ... }; Calling the first (and only) delegate in the "handlers" list fails to call my delegate code. If I change the function to the following (changes highlighted): Event opOpAssign(string op)(void delegate() handler) { static if (op == "+") { >>> auto wrapper = (Object o, EventArgs e) { handler(); }; >>> handlers.insert(wrapper); return this; } else static assert(0, "Operator "~op~" not implemented"); } It works without any problem. Why is this? (In case you're wondering, I'm wanting the ability to pass in a delegate accepting no arguments, in place of a delegate accepting an Object and an EventArgs.) |
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