hi, after reading Re^2: Array question i got surprised and (other then RTFM as suggested by GrandFather) i tried to do some test.

  • in use strict if you declare my $a before the sort you'll get a compile time error; so there are no risk of using $a or $b. i tought it could be frustrating if, later, you need to use a sort and you have to change $a and $b, but you can: sort {$::a cmp $::b} @array and you can avoid the frustration.

  • without use strict instead, all went fine. so i suspected a trap here! the value of $a and $b could had be changed in the sort!
    but seems to me they are local and the old value is kept.

    • Am i wrong or the "magicness" of $a and $b is only matter of compilation semantic?
    does that mean we have not to be worried about using $a and $b, but only reckon the compile time error while use strict?

    Oha

    disclaimer: i want not encourage the use $a and $b, but i would like to understand more the inners of perl and what happen if they are used.

    In reply to magic $a, $b and sort by oha

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