[Issue 8336] Default function parameters ignored by delegate

[d-bugmail]

http://d.puremagic.com/issues/show_bug.cgi?id=8336


bearophile_h...@eml.cc changed:

   What|Removed |Added

 CC||bearophile_h...@eml.cc


--- Comment #1 from bearophile_h...@eml.cc 2012-07-02 05:09:54 PDT ---
Default arguments were never reliable for functions called trough a pointer, so
this little change is expected, take a look at the changelog of 2.060alpha. I
suggest to close this bug report...

-- 
Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email
--- You are receiving this mail because: ---

[Issue 8336] Default function parameters ignored by delegate

[d-bugmail]

http://d.puremagic.com/issues/show_bug.cgi?id=8336



--- Comment #2 from Puneet Goel pun...@coverify.org 2012-07-02 05:32:59 PDT 
---
 Default arguments were never reliable for functions called trough a pointer, 
 so
 this little change is expected, take a look at the changelog of 2.060alpha.

I think it would be cool if default arguments could be maintained for
corresponding delegates too.

I am too naive right now to find out which entry in the changelog are you
pointing too. I tried but could not find anything obvious (to me).

-- 
Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email
--- You are receiving this mail because: ---

[Issue 8336] Default function parameters ignored by delegate

[d-bugmail]

http://d.puremagic.com/issues/show_bug.cgi?id=8336


Jonathan M Davis jmdavisp...@gmx.com changed:

   What|Removed |Added

 Status|NEW |RESOLVED
 CC||jmdavisp...@gmx.com
 Resolution||DUPLICATE


--- Comment #3 from Jonathan M Davis jmdavisp...@gmx.com 2012-07-02 08:34:37 
PDT ---
Given how default arguments work, they make _no_ sense for either function
pointers or delegates. All that happens with a default argument is that when
you call the function, if you don't provide a value for the parameter with a
default argument, the default argument is inserted for you. It's not part of
the function's type. It doesn't result in multiple functions being declared.
So, if you do

void foo(int value = 5) {...}
auto funcPtr = foo;

you've lost the information about the default argument. You simply have

void function(int value) funcPtr;

You could reassign it like so

void bar(int number) {... }
funcPtr = bar;

because the types are identical. The default argument has zero effect on the
type. The situation does not change if you're dealing with a delegate rather
than a function pointer. Function pointers and delegates just don't have
anything to do with default arguments.

There's further discussion on this in bug# 4208, which was ultimately closed as
a duplicate of bug# 3646 - both of which relate to stuff compiling when it
shouldn't due to issues with default arguments.

*** This issue has been marked as a duplicate of issue 3646 ***

-- 
Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email
--- You are receiving this mail because: ---