I tried the following thing: swap 2 vars this way: 
($b,$a) = ($a,$b) ;

[download]
Other way: 
my $tmp = $b ; 
$b= $a ; 
$b = $tmp ;

[download]
If doing this with 2 big vars ( my $a = "10"x10000 ; in a long loop ( 10000 iterations) I can see different results. Case 2, while taking more memory, is kinda faster. In particular it uses up way less cpu time, while case 1 takes a lot of user time. Can somebody explain this ?
also, if I do my ($b,$a) = ($a,$b) It is way faster... ????

In reply to swapping vars, two ways, 2 results... by Sihal

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