Hello Monks,

I am unable to figure out the issue with my code.
I am passing an object to a subroutine - '_predecessors_complete' below, however, I get the following error in a certain case, marked below in the code with '--this line --' -

Can't use an undefined value as a HASH reference at Steps.pm line 264, <OEM2015FLAG> line 1.

The case occurs when I pass in a 'job' value that doesn't exist in the hash of all jobs. So, I tried checking if the job exists in the hash, using the 'if' exists' code.

Question is, which value exactly would be undefined for me to get this error message? I am printing $p here, and it is definitely defined.

OUTPUT -
p : JOBNAME1

Can't use an undefined value as a HASH reference at Steps.pm line 264, <OEM2015FLAG> line 1.

CODE - 


my $rv = $self->_predecessors_complete( $self->predecessors ); ##$self
+->predecessors is a reference to a hash 


sub _predecessors_complete {
    my ( $self, $predecessors ) = @_;

    while ( my $p = shift  @{ $predecessors } ) {

    print "\np : $p\n";


 --this line --      if ( ! exists $self->steps->{$p} ) {
          print "\nThe job $p has not been defined in the Scheduler!\n
+";
          return(100);
        } else {

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In reply to Unable to figure out - undefined value as a HASH reference by Audar

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