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72

Boolean Values

• Testing against 1 is sometimes simply wrong

• For example, perlfunc says that -s tests if "File has nonzero size"

     die "File is empty" unless -s $file == 1;    # WRONG
     die "File is empty" unless -s $file;         # right

• It's always silly

        if (($foo == 12) == 1) { ... }

• Why not this?

        if ((($foo == 12) == 1) == 1) { ... }

• Or this?

        if (((($foo == 12) == 1) == 1) != 0) { ... }

• Distinguish between booleans and numbers

• I fixed all of these and indented correctly; the result is recurse2.pl

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Copyright © 2002 M. J. Dominus