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String Interpolation of Constants in Perl 5

Kirk Lewis on October 01, 2018

This post demonstrates how to use Perl 5 constants with String Interpolation and Regular Expressions. I will briefly explain how String Interpolati...
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Gerard Ribugent Navarro •

I didn't know this way to interpolate variables using this notation, also I thought it was impossible to interpolate constants, for this reason at the work we switched from const pragma to Readonly as suggested by the ProhibitConstantPragma perl critic policy

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E. Choroba •

The important feature of constants is that they are inlined during the compile time, unlike Readonly. Interestingly,

"${ \CONSTANT }"

still inlines the value, but not the reference and dereference:

$ perl -Mconstant=ABC,42 -MO=Deparse -e 'print ABC, "${\ABC}"'
print '42', "${\'42';}";