On or about 4/26/10 1:22 PM, thus spake "Greg Parker" <gpar...@apple.com>:
> On Apr 26, 2010, at 1:01 PM, Matt Neuburg wrote: >> Here's my test: >> MyClass: >> - (void) tryme: (NSString*) s; >> MyClass2: >> - (void) tryme: (NSArray*) s; >> MyClass* thing = [[MyClass alloc] init]; >> NSString* s = @"Howdy"; >> [(id)thing tryme: s]; >> > In this test, the mismatch is an NSString* parameter vs an NSArray* parameter. > That mismatch is "safe": the compiled code for the call site looks the same > either way. The compiler does not warn about this by default. Thanks for this extensive reply; it taught me a lot. Here's something interesting. If I reverse the declaration order of MyClass and MyClass2, like this: >> MyClass2: >> - (void) tryme: (NSArray*) s; >> MyClass: >> - (void) tryme: (NSString*) s; >> MyClass* thing = [[MyClass alloc] init]; >> NSString* s = @"Howdy"; >> [(id)thing tryme: s]; ...Now the compiler *does* complain about that last line - it ways I'm passing a string when an array was expected. So I guess the compiler treats the *first* declaration of a method name-and-signature that it encounters as the "real" one. Now, that's okay, I guess (especially since there's a warning I can turn on to detect even this level of conflict - thanks for explaining about that), as long as the compiler is correctly foreshadowing the behavior of the runtime. I take it from what you say about the compiled code being the same that it is... m. -- matt neuburg, phd = m...@tidbits.com, http://www.tidbits.com/matt/ pantes anthropoi tou eidenai oregontai phusei Among the 2007 MacTech Top 25, http://tinyurl.com/2rh4pf AppleScript: the Definitive Guide, 2nd edition http://www.tidbits.com/matt/default.html#applescriptthings Take Control of Exploring & Customizing Snow Leopard http://tinyurl.com/kufyy8 RubyFrontier! http://www.apeth.com/RubyFrontierDocs/default.html TidBITS, Mac news and reviews since 1990, http://www.tidbits.com _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
