Path: utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!samsung!munnari.oz.au!frankland-river!pem
From: pem@frankland-river.aaii.oz.au (Paul E. Maisano)
Newsgroups: comp.lang.perl
Subject: Are only simple scalars allowed in "do SUBROUTINE (LIST)" ?
Message-ID: <1211@frankland-river.aaii.oz.au>
Date: 4 Mar 90 11:25:36 GMT
Organization: Australian AI Institute
Lines: 27

The manual section for "do SUBROUTINE (LIST)" says:
	SUBROUTINE may be a scalar variable, ... The parentheses are
	required to avoid confusion with the "do EXPR" form.

I always assumed that an array reference could be considered a scalar.
In particular I thought the following was allowed.

#!/usr/bin/perl
sub sub1 {print "1\n";}
sub sub2 {print "2\n";}
@subs = ('sub1', 'sub2');
do $subs[1]();

Unfortunately it gives a syntax error.

I think this is a pity. It is a useful thing to be able to do.
Allowing an arbitrary EXPR instead of a scalar would be even better :-)

Of course, we could always just use eval instead.
Not as elegant though (or as efficient, maybe).

------------------
Paul E. Maisano
Australian Artificial Intelligence Institute
1 Grattan St. Carlton, Vic. 3053, Australia
Ph: +613 663-7922  Fax: +613 663-7937
Email: pem@aaii.oz.au   UUCP: {uunet,mcsun,ukc,nttlab}!munnari!aaii.oz.au!pem