Argel,

What I think ikegami is trying to point out is this one statement from perldoc:

List values are denoted by separating individual values by commas (and enclosing the list in parentheses where precedence requires it)

The only reason the following code doesn't work: 

 perl -MData::Dumper -e '%hash = bob => 90, sue => 12; print Dumper(\%
+hash);'
$VAR1 = {
          'bob' => undef
        };

[download]
...is because of operator precedence.

If we look at the operator precedence table we see that assignment "=" comes in at 19 whereas fat comma "=>" and comma "," come in at 20. So in other words, the %hash = bob gets evaluated before the bob => 90, sue => 12 part.

Up until several minutes ago, when I tried to figure out what ikegami was getting at, I never realized this either. I just blindly memorized and used the (LIST) idiom without understanding why.

So despite ikegami's seeming inscrutability, I thank him for the new insight.

In reply to Re^20: Why? (each...) by jffry
in thread Why? (each...) by locked_user sundialsvc4

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