From: Gary Wright <gwtmp01@...>
Date: 2011-06-20T07:01:52+09:00
Subject: Re: CORE - Inconsistent Handling of Uninitialized Variables

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On Jun 15, 2011, at 5:00 PM, Ilias Lazaridis wrote:
>=20
> I don't understand, why "p $xx" does not fail with and "not defined"
> error.

Because the parser 'sees' the variable $xx and defines it before "p $xx" =
gets executed.

This behavior is different than the local variable case because global =
variables can be discovered by their name alone (i.e. they start with =
'$').  This is a syntactic property that the parser can take advantage =
of.  That property doesn't exist for local variables because, in some =
contexts, they are indistinguishable syntactically from a zero-argument =
method call.  Consider these examples separately and not as part of a =
single snippet of code:

  a =3D b    # 'a' is clearly a local variable while 'b' could be a =
local variable or a zero-argument method call

  c =3D d()  # 'd()' is clearly a zero-argument method call and *not* a =
local variable, 'c' is a local variable

  do_something_with(x,y,z)     # x,y, and z could be method calls or =
variables


Gary Wright=

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