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

delinde · Aug 29, 2012

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

rharsh · Aug 30, 2012

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

Code:

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
}

predamarcel · Sep 5, 2012

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.

BR,
Marcel

___

http://www.notnull.ro/log

____

NateBro · Nov 21, 2012

now thats real short predamarcel!

~Nate_Bro

http://www.setapartgraphics.com/

http://www.setapartgraphics.com/Free_Scripts/

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

delinde

Programmer

rharsh

Technical User

predamarcel

IS-IT--Management

NateBro

Programmer

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