For instance: 
my ( @a, @b );
@a = ( 1, 2, 3 );

foreach ( 0 .. $#a ) { }

[download]
Walks the values 0, 1 and 2. 
foreach ( 0 .. $#b ) { }

[download]
does nothing. But $#b returns -1 because there are no values in it. If it would count down, It'd walk the values 0 and -1.
Ordinary morality is for ordinary people. -- Aleister Crowley

In reply to Re: literal lists by phaylon
in thread literal lists by danmcb

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