Re: super-simple regex-based template eval --- handling undefined substitutions

Does the following help?

use Modern::Perl;
use warnings FATAL => qw{ uninitialized };

my $abc = "ABC";
my $def = "DEF";
## no $ghi is defined.
my $jkl = 0;

my $funnystring = 'hello $abc and $def and $ghi and $jkl';
$funnystring =~ s/(\$\w+)/defined eval $1 ? eval $1 : "unknown $1" /ge
+;
print $funnystring;
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Output:

hello ABC and DEF and unknown $ghi and 0
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Update: Changed from single to double quotes (i.e., "unknown $1") in the ternary operator to show unknown $ghi in output instead of unknown $1.

Comment on Re: super-simple regex-based template eval --- handling undefined substitutions Select or Download Code

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Re^2: super-simple regex-based template eval --- handling undefined substitutions by iaw4 (Monk) on Sep 15, 2012 at 22:40 UTC
yes, it does help. thanks. of course, it would be nicer if unknown $1 were to become 'unknown $ghi'. but it's a great one-liner, nonetheless.	[reply]
Re^3: super-simple regex-based template eval --- handling undefined substitutions by Kenosis (Priest) on Sep 15, 2012 at 22:50 UTC
Using double quotes in the ternary operator will achieve this. Have updated the code to do this...	[reply]