parameter passing problem

gokhan has asked for the wisdom of the Perl Monks concerning the following question:

hello, I have a problem with the parameter passing mechanism among 2 subroutines. my code is as follows.

I have 2 subroutines. the first one takes 2 parameters from command line:
* text file name containing file list
* file format

then it reads the given file, and fetches individual file names (with full path).

then it passes a file path and format to second subroutine called test_format. but these parameters becomes "unreadable" from the array object containing parameters, when I try to convert this array to an hash object (args2hash). because when I print the array object, it gives this output.

"/abc/def/xyz.dat format dat"

Actually it should be like this:

"input /abc/def/xyz.dat format dat"

The "input" keyword is missing.

What should I do?

sub test_filelist_format {
    my $obj = shift;
    my $args = Parser::args2hash (@_);
    
    my $input = $args->{'input'};
    my $format =  $args->{'format'};

    if (!$input || !$format) {
    die("input file or format missing!\n");
    }
    
    ## if not list readable, return -1
    if ( $obj->is_readable(file=>$input) < 0 ) {return -1}

    ...

    my $formatstatus = test_format ("input" => $line, "format" => $for
+mat); 

    ...

}

sub test_format {

    my $obj = shift;
    my $args = Parser::args2hash (@_);

    my $input = $args->{'input'};
    my $format =  $args->{'format'};
    my $gzip = $args->{'gzip'};
    my $columns = $args->{'columns'};

    if (!$input || !$format) {
    die("input file or format missing!\n");
    }

    if ( $obj->is_readable(file=>$input) < 0 ) {return -1};

    ...
}
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Re: parameter passing problem by kcott (Archbishop) on Jul 02, 2013 at 15:38 UTC
G'day gokhan, Welcome to the monastery. You've written both `test_filelist_format()` and `test_format()` as instance methods. If that's what they're supposed to be, you should invoke them like this: `$object->method(@args)` [download] If they're supposed to be just normal subroutines, you'd call them like this: `function(@args)` [download] and you should remove this line: `my $obj = shift;` [download] You haven't shown sufficient code for me to advise which way around these should be: I see no use of `$obj` in either but you've omitted code from both so maybe `$obj` is used where you've shown "`...`". Regardless, that should be enough information for you to fix your current problem. I'd recommend you look in other parts of your code for similar issues. -- Ken	[reply] [d/l] [select]
Re^2: parameter passing problem by gokhan (Initiate) on Jul 03, 2013 at 13:03 UTC
problem solved :) thanks for advise	[reply]
Re^2: parameter passing problem by gokhan (Initiate) on Jul 03, 2013 at 09:20 UTC
$obj is not important for here. Because it gives error before coming to lines of $obj usage. I've updated the code. I added both the lines for $obj and args2hash function.	[reply]
Re^2: parameter passing problem by gokhan (Initiate) on Jul 03, 2013 at 12:55 UTC
Sorry, I didn't know the function of "shift". I am new in Perl. Ok, the problem may be the shift operation.	[reply]
Re^3: parameter passing problem by toolic (Bishop) on Jul 03, 2013 at 12:58 UTC
Perl documentation is available online (shift) and at your command prompt: `perldoc -f shift` [download]	[reply] [d/l]
Re: parameter passing problem by Loops (Curate) on Jul 02, 2013 at 15:01 UTC
If you add a debugging display in test_format to show the contents of the $obj variable, you should see that it contains the word "input"	[reply]
Re: parameter passing problem (in mystery code) by Anonymous Monk on Jul 02, 2013 at 14:58 UTC
What should I do? Fix your code so it isn't broken, fix Parser::args2hash	[reply]