in reply to A more concise way to map the contents of an array.

you could use the conditional operator aka "ternary operator" :

my @cell_contents = map { $_ ? 1 : 0 } @$array_ref[3..10];

another idea is to use doubled negation "!!" and to map the empty string (false) to 0.

my @cell_contents = map { 0 + !!$_ } @$array_ref[3..10];

but I don't think this conciseness justifies the loss of readability.¹

Cheers Rolf

¹) well if you really need 0 for false.

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Re^2: A more concise way to map the contents of an array.
by muba (Priest) on Dec 30, 2012 at 13:23 UTC

    I don't think it gets much more concise than that. However, yet another way to achieve the same would be

    @cell_contents = map { $_ and 1 or 0 } @$array_ref[3..10]

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Re^2: A more concise way to map the contents of an array.
by Amblikai (Scribe) on Dec 30, 2012 at 13:43 UTC

    I like the first one you wrote, i hadn't come across that operator. Seems exactly the same as a conditional statement in Verilog. So it's still pretty readable to me!

    Regarding your footnote, supposing i didn't need 0 for false, how would i do it? And how else can you represent false?

    Thanks very much for your very helpful reply.

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      > Regarding your footnote, supposing i didn't need 0 for false, how would i do it? And how else can you represent false?

      Just use the product of a doubled negation to get clear booleans!¹

      Perl's definition of false covers different data types and context cases.

      from perldata

             A scalar value is interpreted as TRUE in the Boolean sense if i
+t is not
       the null string or the number 0 (or its string equivalent, "0")
+.  The
       Boolean context is just a special kind of scalar context where 
+no
       conversion to a string or a number is ever performed.

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      (Null string here means either empty string "" or undef)

      from perlsyn

      Truth and Falsehood
 
       The number 0, the strings '0' and '', the empty list "()", and 
+"undef"
       are all false in a boolean context. All other values are true.
       Negation of a true value by "!" or "not" returns a special fals
+e value.
       When evaluated as a string it is treated as '', but as a number
+, it is
       treated as 0.

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      Cheers Rolf

      ¹) in this case  my @cell_contents = map { !!$_ } @$array_ref[3..10];

      for me the most readable alternative!

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        So just to be clear, if i double negate something, i'll lose the original "value" and be left with the pure boolean representation of the data? That could prove useful!

        Thanks again for your reply!

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