lets say i have a subroutine i want to pass a variable, and the sub should modify it, this would normally require passing a refreence: 
#define the sub
sub strip_space
{
    # get our parameter
    my $val = $_[0];

    # if not given a reference, return false
    return false if ref($val) ne "SCALAR";

    # remove whitespace and retrn true on success
    $$val =~ s/\s+//g;
    return 1;
}

# and call said sub
$test = "this will have no spaces!";
print $test if strip_space($test);
print $test if strip_space(\$test);

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the first print would never take place because a reference isnt passed to the sub, so it returns false, whereas the second print would work as expected. i remember to pass it a reference to a variable rather than just the variable itself.

but is there a way to not have to explicitly pass a reference to the sub? isnt there a way i can just use strip_space($test) every time and from within the sub grab a reference to $test?

In reply to get a reference implicitly within a subroutine call? by Anonymous Monk

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