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$1 - can it be 'reset to null' ?

$1 - can it be 'reset to null' ?

$1 - can it be 'reset to null' ?

If you are doing RegEx work, and you want to be sure that $1 is null, you cannot do this:

$1 = "";     ## This will produce an error:  $1 is read only

But you can do this:

m/()()()/;     ## will reset $1, $2 and $3 to be nothing

HTH, delinde

RE: $1 - can it be 'reset to null' ?

Another approach, rather than checking to see if there is a value in $1, $2 and $3, could be to do something like:


if ($someVar =~ m/(.)(..)(...)/) {
    # execute this block if the regex succeeds
    # also means $1, $2 and $3 were set
} else {
    # regex did not match - execute this block

RE: $1 - can it be 'reset to null' ?

Hi there,

The sortest way to reset all $N variable is to call for a match like:
This will ever be successful and all the matching vars are reset.



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