From mboxrd@z Thu Jan  1 00:00:00 1970
From: Harald van Dijk <harald@gigawatt.nl>
Subject: Re: static vs. dynamic scoping
Date: Sun, 14 Nov 2010 01:09:55 +0059
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Cc: =?UTF-8?B?0L7Qu9GM0LPQsCDQutGA0YvQttCw0L3QvtCy0YHQutCw0Y8=?= <olga.kryzhanovska@gmail.com>, Eric Blake <eblake@redhat.com>

On 14/11/10 00:54, =D0=BE=D0=BB=D1=8C=D0=B3=D0=B0 =D0=BA=D1=80=D1=8B=D0=
=B6=D0=B0=D0=BD=D0=BE=D0=B2=D1=81=D0=BA=D0=B0=D1=8F wrote:
> Now function a uses typeset IFS=3D"X" to set the field separator to "=
X"
> via a local variable IFS. If function b now uses "read foo1 foo2 foo3=
"
> to read a line of a database the concept of dynamic scoping *BITES*.

The way I had seen "local IFS" used is to sanitise IFS -- to reset IFS=20
to the default value, when IFS was set to, for example, : before the=20
function was called, and the function wants to split on whitespace. In=20
that case, you don't want b to get IFS=3D:. Both forms are used, and in=
=20
your form, I agree, static scoping is more useful.