delegate syntax

  • Thread starter Thread starter Rick Lones
  • Start date Start date
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Rick Lones

When I declare a delegate signature thusly . . .

private delegate void eventHandler(EventWaitHandle ewh);

. . . can someone explain why the "ewh" identifier is required? It appears
completely superfluous to me - the parameter type(s) and position(s) seem like
all that should be needed. This is .Net 2.0 BTW, dunno what changes in later
incarnations.

-rick-
 
When I declare a delegate signature thusly . . .

private delegate void eventHandler(EventWaitHandle ewh);

. . . can someone explain why the "ewh" identifier is required? It
appears completely superfluous to me - the parameter type(s) and
position(s) seem like all that should be needed. This is .Net 2.0 BTW,
dunno what changes in later incarnations.

-rick-
Click to expand...

I think it is also the same with interface declaration where the method
identifier is superfluos, but actualy I prefer that way because I know
what that parameter supposed to means (which improve readability).
 
Peter said:
It's the same in all versions of the language. And yes, the parameter
name is theoretically superfluous. However, note that delegate types
use the same data structure to define the signature as for methods, the
MethodInfo type (which you can retrieve from the delegate type by
getting the MethodInfo for the Invoke() method on the type), and the
MethodInfo type has to include parameter names.

I suppose the compiler could have just put in some placeholders, but it
seems to me that for those moments when one is in fact looking at the
parameter names (either in the type declaration or via reflection),
having meaningful parameter names is very useful. The type alone is
often insufficient to explain how a parameter should be used (e.g.
"sender" in the EventHandler delegate type).
Click to expand...

It's been so long I had to peek at an old C header file to be sure that the
parameter was not required in, e.g., an extern declaration. It seems basically
an artifact then but one of "intelligent design". I do see some advantages,
especially as regards your point re MethodInfo. Thanks.

-rick-
 
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