Question

I have a setter sub setAssignmentStatus which takes an array of hashes (AoH from here on) and another parameter (do not concern yourself with this as that part works), and does something iterating through the AoH to set another entry in each hash element. It does not return anything because I want to use the same AoH object with the added entries after it is pulled through the setter sub and not construct a whole new AoH and repopulate the entries. Here is the setter:

sub setAssignmentStatus
{
    my $fileFlatArySclr = $_[0];
    my $cfgFile = $_[1];

    #here I convert the AoH from the scalar necessary for the sub to its native form
    my @fileFlatAry = @$fileFlatArySclr;

    #this works, don't worry
    my %cfgVarHash = getConfigVars($cfgFile);

    foreach my $fileVarHashSclr(@fileFlatAry)
    {
        #convert each AoH entry from scalar necessary for iteration to native hash
        my %varHash = %$fileVarHashSclr;

        my $varName = $varHash{'VAR_NAME'};

        my $asgnLineCnt = $varHash{'ASGN_CNT'};

        my $asgnSts;
        my $fileAsgnSts; 
        my $cfgAsgnSts; 

        if($asgnLineCnt > 0) { $fileAsgnSts = 1; } else { $fileAsgnSts = 0; }

        my $cfgAsgnLine = $cfgVarHash{$varName};

        if($cfgAsgnLine ne undef) { $cfgAsgnSts = 1; } else { $cfgAsgnSts = 0; }

        $asgnSts = $fileAsgnSts.$cfgAsgnSts;

        #debug to make sure $asgnSts is not null in the first place (it is not!)
        print "\n*** setting ASGN_STUS of ".$varName." to ".$asgnSts;

        #Here we set ASGN_STUS for every iteration
        $varHash{'ASGN_STUS'} = $asgnSts;
    }
}

It is called as follows:

setAssignmentStatus(\@fileFlatAry, $cfgFile);

However, after sending the @fileFlatAry AoH through setAssignmentStatus, each element hash does not contain an ASGN_STUS entry. Why is that and how can I fix it?

My suspicion is that I am doing something wrong with the \ modifier, which is how I am getting the data structure to be passed as a scalar parameter to the sub but I am not sure.

Answer 1

You modify %varHash instead of modyfing the referenced hash. Stop copying everything into local variables and modyfying the local variables.

$varHash{'ASGN_STUS'} = ...;

should be

$fileVarHashSclr->{'ASGN_STUS'} = ...;

I wouldn’t do my @fileFlatAry = @$fileFlatArySclr; either. Pure waste.