Let's have a look at the '\', ' []' and '()' constructs:
- [$a, $b, $c] is a reference to an array with
three scalar elements.
- \[$a, $b, $c] is a reference to a scalar,
which againg is a reference to an array with three scalar
elements.
- [\$a, \$b, \$c] is a reference to an array with
three scalars. Each of theese three scalars is a reference
to the real scalar.
So using the special braces ' [' and ' ]' creates a reference to an array.
If you use the normal braces '(' and ')' you group things into lists, so:
- ($a, $b, $c) is a list of three scalar elements.
It is not an array, but a list.
- \($a, $b, $c) is a list of three scalar elemnts.
Each of theese three elements is a reference to the real scalar
(that is your value "foo", "bar" and "baz")
- (\$a, \$b, \$c) is excatly the same as \($a, $b, $c).
The '\' operator will distribute over the list.
So if we use the [$a, $b, $c] construct our list @list will contain
one element, namely a reference to an array.
If we on the other hand use the ($a, $b, $c) construct, the list
will contain 3 elements.
So then, an easier way to write [\$a, \$b, \$c] would
be [ \($a, $b, $c) ].
But still, this will not fix your example - I hope you can see the
error in the example, but let's fix it:
$a = "foo";
$b = "bar";
$c = "baz";
@list = \($a, $b, $c);
foreach(@list) { print $$_ . "\n"; }
Autark.
In reply to RE: \($a, $b, $c) eq (\$a, \$b, \$c), is \$a, $b, $c eq \$a, \$b, \$c?
by autark
in thread \($a, $b, $c) eq (\$a, \$b, \$c), is \$a, $b, $c eq \$a, \$b, \$c?
by Anonymous Monk
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