From: ahoward <ahoward@...>
Date: 2003-02-01T03:27:10+09:00
Subject: Re: Local variables & blocks

On Sat, 1 Feb 2003, Yukihiro Matsumoto wrote:

> The "defined?" status resolved at compile time, so that this never be
> true, even after the first iteration, since there's no preceding
> assignment to the variable "bar".

to clarify (for my sake), vairables are _always_ resolved lexically and _never_
dynamically?

eg.

dynamic resolution

  ~/eg/ruby > cat foo.rb
  code = ARGV.shift
  p code
  eval code
  p (eval 'x')

  eg/ruby > ruby foo.rb 'x = 42'
  "x = 42"
  42

lexical resolution

  eg/ruby > cat foo.rb
  code = ARGV.shift
  p code
  eval code
  p (x)
  eg/ruby > ruby foo.rb 'x = 42'
  "x = 42"
  foo.rb:4: undefined local variable or method `x' for #<Object:0x401909fc>
  (NameError)


-a

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