Re^2: What I Most Recently Learned in Perl, But Should Have Already Known

perl -MO=Deparse -e ' print "true" if 1'

If we do if 0 something even funnier happens:

$ /usr/bin/perl -MO=Deparse -e 'print "true" if 0'
'???';
[download]

But which is most amusing is the fact that the deparsed code generates a warning:

$ /usr/bin/perl -w -e 'print "true" if 0'
$ /usr/bin/perl -w -e '"???"'
Useless use of a constant in void context at -e line 1.
[download]

--
David Serrano

Comment on Re^2: What I Most Recently Learned in Perl, But Should Have Already Known Select or Download Code

Replies are listed 'Best First'.
Re^3: What I Most Recently Learned in Perl, But Should Have Already Known by pKai (Priest) on Aug 23, 2006 at 09:36 UTC
`'???'` actually is no real thing. It's more like `Deparse` saying, this should be optimized away. E. g. every "`Useless use of a constant in void context`" also results in this.	[reply] [d/l] [select]

In Section Meditations