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This is an excerpt from the latest version perlfaq4.pod, which
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4.37: What's wrong with always quoting "$vars"?

The problem is that those double-quotes force stringification--coercing
numbers and references into strings--even when you don't want them to be
strings. Think of it this way: double-quote expansion is used to produce
new strings. If you already have a string, why do you need more?

If you get used to writing odd things like these:

print "$var"; # BAD
$new = "$old"; # BAD
somefunc("$var"); # BAD

You'll be in trouble. Those should (in 99.8% of the cases) be the
simpler and more direct:

print $var;
$new = $old;

Otherwise, besides slowing you down, you're going to break code when the
thing in the scalar is actually neither a string nor a number, but a

sub func {
my $aref = shift;
my $oref = "$aref"; # WRONG

You can also get into subtle problems on those few operations in Perl
that actually do care about the difference between a string and a
number, such as the magical "++" autoincrement operator or the syscall()

Stringification also destroys arrays.

@lines = `command`;
print "@lines"; # WRONG - extra blanks
print @lines; # right


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