"map in void context is no longer expensive. map is now context aware, and will not construct a list if called in void context."

Hi Ken, I wasn't referring to "throwing away the output" in terms of wasted resources, but rather in terms of unclear code.

map is a function that returns a list -- when it is used in void context it smells bad, because it forces the reader to double-check that the author didn't make a mistake, falling into the same general category as any other distracting syntax or idiom.

It's also a bad habit in general to use functions for their side effects, as those may change.


The way forward always starts with a minimal test.

In reply to Re^4: Open Filehandle once by 1nickt
in thread Open Filehandle once by Dunkellbusch

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