From: "David A. Black" <dblack@...>
Date: 2007-03-17T12:51:17+09:00
Subject: Re: yield

Hi --

On 3/16/07, Corey Konrad <0011@hush.com> wrote:
> Brian Candler wrote:
> > On Sat, Mar 17, 2007 at 07:10:26AM +0900, Corey Konrad wrote:
> >>
> >> def printer(arg)
> >>   yield arg
> >> end
> >>
> >> printer("ball")
> >> printer {|word| puts word}
> >>
> >> why is that, cant yield be used with arguments?
> >
> > It can. Your second function 'printer' takes one argument plus one
> > block.
> > However in the first case you were calling it without a block, and in
> > the
> > second case you were calling it without an argument.
> >
> > What you need is:
> >
> >   printer("ball") {|word| puts word}
>
>
> oh ok, my understanding for some reason was that the method was going to
> remmeber that i set arg to "ball" so that when i used printer with the
> block that "ball" would still be in arg. So is that why it isnt working,
> is because when i call the printer method the second time the value
> stored in arg is destroyed?

The two calls to printer are unrelated to each other. Each of them
uses a local variable 'arg', but they're two different variables.

The code block is, syntactically, part of the method call.  So if
there's no block for a given method call, that's that.


David

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