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my() in Control Structures

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my() in Control Structures
You can now use my() (with or without the parentheses) in the control expressions of control structures such as:

    while (defined(my $line = <>)) {
        $line = lc $line;
    } continue {
        print $line;

    if ((my $answer = <STDIN>) =~ /^y(es)?$/i) {
    } elsif ($answer =~ /^n(o)?$/i) {
    } else {
        chomp $answer;
        die "`$answer' is neither `yes' nor `no'";

Also, you can declare a foreach loop control variable as lexical by preceding it with the word ``my''. For example, in:

    foreach my $i (1, 2, 3) {

$i is a lexical variable, and the scope of $i extends to the end of the loop, but not beyond it.

Note that you still cannot use my() on global punctuation variables such as $_ and the like.

Source: what's new for perl5.004
Copyright: Larry Wall, et al.
Next: pack() and unpack()

Previous: keys as an lvalue

(Corrections, notes, and links courtesy of RocketAware.com)

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