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    <p>Perl allows you to choose your own quote delimiters. If you find you need to use a double quote inside of an interpolating string (i.e. <code>""</code>) or single quote inside of a non-interpolating string (i.e. <code>''</code>) you can use a <a href="http://perldoc.perl.org/perlop.html#Quote-and-Quote-like-Operators" rel="noreferrer">quote operator</a> to specify a different character to act as the delimiter for the string. Delimiters come in two forms: bracketed and unbracketed. Bracketed delimiters have different beginning and ending characters: <code>[]</code>, <code>{}</code>, <code>()</code>, <code>[]</code>, and <code>&lt;&gt;</code>. All other characters<code>*</code> are available as unbracketed delimiters.</p> <p>So your example could be written as</p> <pre><code>$foo = qq(12."bar bar bar"|three); </code></pre> <p>Inserting text after "12." can be done many ways (<a href="http://en.wikipedia.org/wiki/There_is_more_than_one_way_to_do_it" rel="noreferrer">TIMTOWDI</a>). A common solution is to use a <a href="http://perldoc.perl.org/perlop.html#s/PATTERN/REPLACEMENT/msixpogce" rel="noreferrer">substitution</a> to match the text you want to replace.</p> <pre><code>$foo =~ s/^(12[.])/$1../; </code></pre> <p>the ^ means match at the start of the sting, the <code>()</code> means capture this text to the variable <code>$1</code>, the <code>12</code> just matches the string <code>"12"</code>, and the <code>[]</code> mean match any one of the characters inside the brackets. The brackets are being used because <code>.</code> has special meaning in regexes in general, but not inside a character class (the <code>[]</code>). Another option to the character class is to escape the special meaning of <code>.</code> with <code>\</code>, but many people find that to be uglier than the character class.</p> <pre><code>$foo =~ s/^(12\.)/$1../; </code></pre> <p>Another way to insert text into a string is to assign the value to a call to <a href="http://perldoc.perl.org/functions/substr.html" rel="noreferrer"><code>substr</code></a>. This highlights one of Perl's fairly unique features: many of its functions can act as lvalues. That is they can be treated like variables.</p> <pre><code>substr($foo, 3, 0) = ".."; </code></pre> <p>If you did not already know where <code>"12."</code> exists in the string you could use <a href="http://perldoc.perl.org/functions/index.html" rel="noreferrer"><code>index</code></a> to find where it starts, <a href="http://perldoc.perl.org/functions/length.html" rel="noreferrer"><code>length</code></a> to find out how long "12." is, and then use that information with <code>substr</code>.</p> <p>Here is a fully functional Perl script that contains the code above.</p> <pre><code>#!/usr/bin/perl use strict; use warnings; my $foo = my $bar = qq(12."bar bar bar"|three); $foo =~ s/(12[.])/$1../; my $i = index($bar, "12.") + length "12."; substr($bar, $i, 0) = ".."; print "foo is $foo\nbar is $bar\n"; </code></pre> <p><code>*</code> all characters except whitespace characters (space, tab, carriage return, line feed, vertical tab, and formfeed) that is</p>
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    1. POHow can I insert text into a string in Perl?
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    1. COIf you keep writing answers this detailed (and given how busy you already are on the Perl Beginners mail list), I doubt you'll get any work done at all. Luckily, SO doesn't have a big volume of Perl questions...
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    2. COHeh, you may notice may attendance at PB waxes and wanes. I tend to go to PB when I either have little to do, or I am so frustrated I can't get any real work done anyway. All of this is part of my training myself to be a trainer (which is why I go for the hyper-detailed answers).
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    3. COThat's a heck of an answer.
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