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Re^4: How to check if a variable's value is equal to a member of a list of values

by LanX (Chancellor)
on Mar 26, 2013 at 21:37 UTC ( #1025590=note: print w/replies, xml ) Need Help??


in reply to Re^3: How to check if a variable's value is equal to a member of a list of values
in thread How to check if a variable's value is equal to a member of a list of values

grep { TEST } LIST is semantically equivalent to map { TEST ? $_ : () } LIST

Seems obvious that more logic results in longer runtime.

Don't you think so?

Cheers Rolf

( addicted to the Perl Programming Language)

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Re^5: How to check if a variable's value is equal to a member of a list of values
by dbuckhal (Pilgrim) on Mar 26, 2013 at 22:55 UTC
    Yes, I would agree that more logic increases runtime, but from your example, are you saying that grep should be faster? Please explain your example, so I understand you clearly.

    Personally, I have no idea how grep, map, or ~~ all work "under the hood". In your syntax, I see grep and map both iterating over the list, so my guess was they would have performed equally. I was surprised at my results.
      > are you saying that grep should be faster?

      no I'm showing that grep {TEST} is more complex than map {TEST}

      Cheers Rolf

      ( addicted to the Perl Programming Language)

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