note
imp
There is no runtime difference unless there is a variable being interpolated, in which case only double quotes are appropriate. The perl parser treats them the same otherwise:
<code>
perl -MO=Deparse -e ' $a = "foo"; $b = ''foo''; $c = q{foo}'
$a = 'foo';
$b = 'foo';
$c = 'foo';
</code>
<code>
perl -MO=Deparse -e ' $a = "$foo"; $b = q{$foo};'
$a = "$foo";
$b = '$foo';
</code>
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