You can also leave off the else branch, in which case map would return the empty string (not sure why not undef) when the if-condition isn't true...     (Emphasis added)

See Re: Map Function Weirdness and Re: Map Function Weirdness (and ikegami's elaboration thereto Re^2: Map Function Weirdness) to Map Function Weirdness.

In reply to Re^3: if block inside map by AnomalousMonk
in thread if block inside map by mhearse

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