in reply to A generic sorting problem

I think you should use the cmp and <=> operators in the sort subroutine, like this :
@a = qw( words only contains );
@b = qw( 8 3 7 1 );

print join( " ", sort { $a <=> $b || $a cmp $b } @a ), "\n";
# contains only words
print join( " ", sort { $a <=> $b || $a cmp $b } @b ), "\n";
# 1 3 7 8

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This way you can even sort numbers AND letters : 
@a = qw( 2 two 1 one );
print join( " ", sort { $a cmp $b || $a <=> $b } @a ), "\n";
# 1 2 one two

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Re: Re: A generic sorting problem
by demerphq (Chancellor) on Jul 19, 2002 at 10:25 UTC
    Your first two examples would raise warnings galore when handling non numeric values, and the second example is simply an alphabetic sort, equivelent to sort @a

    use warnings;
use strict;
my @a = qw( 2 two 1 11 12 one 3abcd 6foo );
print join( " ", sort { $a <=> $b || $a cmp $b } @a ), "\n";

__END__
Argument "two" isn't numeric in numeric comparison (<=>) at c:\temp\so
+rt.pl line 4.
Argument "one" isn't numeric in numeric comparison (<=>) at c:\temp\so
+rt.pl line 4.
Argument "3abcd" isn't numeric in numeric comparison (<=>) at c:\temp\
+sort.pl line 4.
Argument "6foo" isn't numeric in numeric comparison (<=>) at c:\temp\s
+ort.pl line 4.
one two 1 2 3abcd 6foo 11 12

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    and 
    #...
print join( " ", sort { $a cmp $b || $a <=> $b } @a ), "\n";

__END__
1 11 12 2 3abcd 6foo one two

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    Yves / DeMerphq
    ---
    Writing a good benchmark isnt as easy as it might look.

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[d/l]
[select]
      Oops :( you are absolutely right !

      But is there a way to do this without getting the warnings messages ? by localizing $^W I guess ? or simply by not using this kind of construction :)))
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