checking a vulue it set

[user]

Is there a way I check is a variable has a been set to a vaule
(without knowing the value)> And can I get how many paramters were
passed to a function, and where from or what called tht funcation?

Finally, is a way to set a break point in a scrtip? I want a scrit to
excute up untill a certain point so I can check certain vaules.

 

[Anno Siegel]

Is there a way I check is a variable has a been set to a vaule
(without knowing the value)

if ( defined $var ) { # $var has been assigned to

And can I get how many paramters were
passed to a function, and where from or what called tht funcation?

sub foo {
my $num_of_args = @_;

For the second question: "perldoc -f caller".

Finally, is a way to set a break point in a scrtip? I want a scrit to
excute up untill a certain point so I can check certain vaules.

See "perldoc perldebug".

Anno