This is frustrating but I can't figure out why it isn't working. I want to replace $1 (the full file name) with whatever the root file name ($2) maps to, based on information stored in a hash. If the mapping doesn't exist, I want to display that result instead. 

s/$1/exists($hash{$2}) ? $hash{$2} : "$2:mapping not done"/e;

[download]
So why do I get 
Use of uninitialized value in concatenation (.) or string

[download]
I expected instead for the !defined condition to trigger the 'mapping not done' string.

The variable %hash is currently empty. I plan to populate it as I go through the files.

Hand is open and facing forehead, ready to move ..

--t. alex
Life is short: get busy!

In reply to Using 'e' in s/// by talexb

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