3.1. q{}, qq{} and Friends
Customary | Generic | Meaning | Interpolates |
---|---|---|---|
'' | q{} | Literal | No. |
"" | qq{} | Literal | Yes |
`` | qx{} | Command | Yes (unless the delimiter is '') |
(none) | qw{} | Word List | No |
// | m{} | Pattern Match | Yes (unless the delimiter is '') |
(none) | qr{} | Declaration of a Regex Pattern | Yes (unless the delimiter is '') |
(none) | s{}{} | Substitution | Yes (unless the delimiter is '') |
(none) | tr{}{} | Transliteration | No |
What it means, is that you can write an interpolated string as qq
followed by a matching wrapping character, inside which the string can be placed. And likewise for the other strings. Here are some examples:
#!/usr/bin/env perl use strict; use warnings; my $h = q{Hello There}; print qq|$h, world!\n|; my $t = q#Router#; my $y = qq($h $h $h $t); $y =~ s!Hello!Hi!; print qq#$y\n#; my @arr = qw{one two three}; for my $i (0 .. $#a) { print "$i: $arr[$i]\n"; }
The output of this is:
Hello There, world! Hi There Hello There Hello There Router 0: one 1: two 2: three
As one can see, the wrapping characters should match assuming they are a left/right pair ({
to }
etc.).