Ruby doesn't implement x++ for Fixnum's because ???
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From: Tony Arcieri on 8 Nov 2009 15:26 [Note: parts of this message were removed to make it a legal post.] On Sun, Nov 8, 2009 at 1:15 PM, Walton Hoops <walton(a)vyper.hopto.org> wrote: > Incorrect. In fact the very first message in this thread provided an > example of redifining Fixnum in such a way that it was mutable. > No it didn't, that post created a new class called "FixNum" And again, that's beside the point, which is to allow the expected "++" semantics for immutable Numerics while also allowing in-place incrementation for other classes which may store a mutable value, such as counters (whose backing store may be a database, memcache, etc) That would provide a truly Ruby-like ++ experience, aside from the fact you can't redefine #++ for a Numeric, which probably isn't a good idea anyway. -- Tony Arcieri Medioh/Nagravision
From: Walton Hoops on 8 Nov 2009 15:54 > -----Original Message----- > From: bascule(a)gmail.com [mailto:bascule(a)gmail.com] On Behalf Of Tony > No it didn't, that post created a new class called "FixNum" I apologize, you are correct that post defined a new class, due to a capitalization error, which was corrected a few posts down. The point is, yes indeed, numerics can be mutable. I could if I were so inclined write a String backed subclass of Numeric which represtend integers as Roman Numerals and was mutable, (or Fixnum backed if we're feeling boring). > And again, that's beside the point, which is to allow the expected "++" > semantics for immutable Numerics while also allowing in-place > incrementation > for other classes which may store a mutable value, such as counters > (whosebacking store may be a database, memcache, etc) But your missing the point that ++ is NOT expected. Not in Ruby. Ruby simply doesn't work that way. You talked about "operator rebinding", but you ignored the fact that ++ is nothing like those examples. a+=<expression> expands to a=a+<expression>. It's a simple syntaxtic sugar. a++ expands to... what? Nothing. There is no way you could expand puts foo(a++,b) and get the desired behavior. This discussion has gone on and on, and it's really quite pointless. There is no good reason to include ++ in Ruby, and every reason not to. No one can even agree on what they would expect a ++ operator to do when used "The Ruby Way", with C programmers expecting it to work like C, and the Rubyists expecting it to follow the Ruby way, with every operator being a method call on that object (NOT variable). So why introduce this operator into the language that would cause all this confusion, when all it will do is save a few C programmers a SINGLE line of code. 95% of the time it won't even do that, if they would learn and do things the Ruby way, rather than trying to write C code in Ruby.
From: Florian Aßmann on 8 Nov 2009 16:30 Gaah, close this thread! ;) Cheers Florian Am 08.11.2009 um 21:26 schrieb Tony Arcieri: > On Sun, Nov 8, 2009 at 1:15 PM, Walton Hoops > <walton(a)vyper.hopto.org> wrote: > >> Incorrect. In fact the very first message in this thread provided an >> example of redifining Fixnum in such a way that it was mutable. >> > > No it didn't, that post created a new class called "FixNum" > > And again, that's beside the point, which is to allow the expected "+ > +" > semantics for immutable Numerics while also allowing in-place > incrementation > for other classes which may store a mutable value, such as counters > (whose > backing store may be a database, memcache, etc) > > That would provide a truly Ruby-like ++ experience, aside from the > fact you > can't redefine #++ for a Numeric, which probably isn't a good idea > anyway. > > -- > Tony Arcieri > Medioh/Nagravision
From: Marnen Laibow-Koser on 8 Nov 2009 16:40 Florian Aßmann wrote: > Gaah, close this thread! ;) I don't think there's a mechanism for doing that, since this is an unmoderated list. You don't have to follow it if you don't want to. :) > > Cheers > Florian > > Am 08.11.2009 um 21:26 schrieb Tony Arcieri: Best, -- Marnen Laibow-Koser http://www.marnen.org marnen(a)marnen.org -- Posted via http://www.ruby-forum.com/.
From: Tony Arcieri on 8 Nov 2009 17:44
On Sun, Nov 8, 2009 at 2:30 PM, Florian Aßmann <florian.assmann(a)email.de>wrote: > Gaah, close this thread! ;) > I suppose the whole discussion is moot as Ruby will likely never see a ++ operator. I was just trying to make clear the limitation wasn't a technical one, and further show how a ++ operator could be "Ruby-like" while still retaining C/C++/Java-like semantics. -- Tony Arcieri Medioh/Nagravision |