In Perl 5.6.1, writing out a little test script i got my error to one little line. Here's the entire script to start with:
#!/usr/bin/perl -w
use strict;

my @one = qw( one two three );
my $two = sub { print "we were passed @_\n" };

# here's the problem line:
$two->( map { anda => $_ } @one );

# But this would work fine:
#$two->( map { 1 && anda => $_ } @one );

[download]

When compiling that as is Perl bails on a syntax error. The second (more ugly) version works fine, as well as using a variable instead of a hard-coded string. That's fine and good, but why is it happening that way?

i would think one would be able to code as i have above, but (on a Solaris 9 machine running the standard Perl 5.6.1 Sun install) apparently not. If i add parentheses i find out that apparently Perl is viewing { anda => $_ } as a hash reference, but map is expecting a code reference, so that's probably where the discrepency comes from.

Questions:

  1. Is there some nuance in the code i'm missing that will make it be short and readable instead of adding ugly hacks to get map to read that as a code block instead of a hash reference?
  2. Is anyone else having this problem? Or is it just me?
  3. Assuming it's standard behavior from 5.6.1, is it fixed in 5.8?
thanks for any and all help...

jynx

In reply to (5.6.1) map mayhem? by jynx

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