From: Rick DeNatale <rick.denatale@...>
Date: 2007-09-24T20:49:27+09:00
Subject: Re: foo || 0 will cause exception but not for himself

On 9/23/07, Phrogz <phrogz@mac.com> wrote:
> On Sep 22, 2:51 pm, 7stud -- <dol...@excite.com> wrote:
> > Gavin Kistner wrote:
> > > On Sep 22, 7:26 am, SpringFlowers AutumnMoon
> > > <summercooln...@gmail.com> wrote:
> > >> so how about just a method not inside a class, can it be named "foo=" as
> > >> well?  if so, how does Ruby know  foo=1 is really an assignment or a
> > >> method call foo=(1)?
> >
> > >> Ruby doesn't seem to like "foo=" as a method:
> >
> > > self.foo = 10
> >
> > def foo=(val)
> >     "hello"
> > end
> >
> > puts self.foo = 10   #10
>
> Er, what's your point? Methods whose names end with a '=' character
> always return the value 'assigned' to them, not the last expression in
> the method. How is that relevant to this discussion of how to invoke
> them, and the scope and determinatino of variables versus methods?

Actually, it's not that, it's the way assignments get parsed/compiled:

irb(main):001:0> class Foo
irb(main):002:1>   def x
irb(main):003:2>     @x
irb(main):004:2>   end
irb(main):005:1>   def x=(val)
irb(main):006:2>     @x = val
irb(main):007:2>     "Surprise"
irb(main):008:2>   end
irb(main):009:1> end
=> nil
irb(main):010:0> f = Foo.new
=> #<Foo:0x7a1fc>
irb(main):011:0> f.x=2
=> 2
irb(main):012:0> f.__send__(:x=, 3)
=> "Surprise"
irb(main):013:0>  f.x
=> 3


-- 
Rick DeNatale

My blog on Ruby
http://talklikeaduck.denhaven2.com/