| PerlFAQ Server 2005-07-27, 9:03 am |
| This message is one of several periodic postings to comp.lang.perl.misc
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4.36: How can I expand variables in text strings?
Let's assume that you have a string that contains placeholder variables.
$text = 'this has a $foo in it and a $bar';
You can use a substitution with a double evaluation. The first /e turns
$1 into $foo, and the second /e turns $foo into its value. You may want
to wrap this in an "eval": if you try to get the value of an undeclared
variable while running under "use strict", you get a fatal error.
eval { $text =~ s/(\$\w+)/$1/eeg };
die if $@;
It's probably better in the general case to treat those variables as
entries in some special hash. For example:
%user_defs = (
foo => 23,
bar => 19,
);
$text =~ s/\$(\w+)/$user_defs{$1}/g;
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