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@@ -39,7 +39,7 @@ lightweight classes to solve the same and many other problems.
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# Delegate
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A delegate can be used as a general purpose invoker with no memory overhead for
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-free functions and member functions provided along with an instance on which to
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+free functions, lambdas and members provided along with an instance on which to
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invoke them.<br/>
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It doesn't claim to be a drop-in replacement for an `std::function`, so don't
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expect to use it whenever an `std::function` fits well. That said, it's most
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@@ -93,9 +93,9 @@ delegate.connect<&g>(c);
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delegate(42);
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```
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-The function `g` is invoked with a reference to `c` and `42`. However, the
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-function type of the delegate is still `void(int)`. This is also the signature
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-of its function call operator.<br/>
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+Function `g` is invoked with a reference to `c` and `42`. However, the function
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+type of the delegate is still `void(int)`. This is also the signature of its
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+function call operator.<br/>
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Another interesting aspect of the delegate class is that it accepts functions
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with a list of parameters that is shorter than that of its function type:
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@@ -106,9 +106,15 @@ delegate(42);
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```
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Where the function type of the delegate is `void(int)` as above. It goes without
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-saying that the extra arguments are silently discarded internally.<br/>
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-This is a nice-to-have feature in a lot of cases, as an example when the
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-`delegate` class is used as a building block of a signal-slot system.
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+saying that the extra arguments are silently discarded internally. This is a
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+nice-to-have feature in a lot of cases, as an example when the `delegate` class
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+is used as a building block of a signal-slot system.<br/>
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+In fact, this filtering works both ways. The class tries to pass its first
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+_count_ arguments **first**, then the last _count_. Watch out for conversion
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+rules if in doubt when connecting a listener!<br/>
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+Arbitrary functions that pull random arguments from the delegate list aren't
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+supported instead. Other feature were preferred, such as support for functions
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+with compatible argument lists although not equal to those of the delegate.
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To create and initialize a delegate at once, there are a few specialized
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constructors. Because of the rules of the language, the listener is provided by
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Michele Caini