Gossamer Forum: General: Perl Programming: Interesting Concatenation Problem

Jul 12, 2010, 11:03 PM

gpta_varun

Novice (24 posts)

Jul 12, 2010, 11:03 PM

Post #1 of 15

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Interesting Concatenation Problem - Require Help

HI All ,

I am facing an interesting problem

Please help me resolve the same.

I have two functions. The main function reads the machine name from an input config file , passes it on to sub_main() function .
In the sub_main() function , I need to concatenate this machine name with ".world" .

However the concatenated string is wierd. However both the inpus to the concatenation are OK , the result is not

Please Help

Attaching code for your reference.

#!/usr/bin/perl

main();

sub main () {

my %config_hash=();
my @machines=();
my $i=0;
open(CONFIG, "<config_details.cfg") || die "I/O Success - Cannot process get_max_ri.sql file";

while (<CONFIG>)
{
my @config_line=split(/=/,$_);
print "$config_line[0]\n";
$config_hash{$config_line[0]}=$config_line[1];
}

@machines=split(/,/,$config_hash{"MACHINE NAMES"});
my $NUM_MACHINES=@machines;

for ($i=0;$i<$NUM_SMF_MACHINES;$i++)
{
chomp($machines[$i]);
sub_main($i+1,$machines[$i]);
}

}

sub sub_main()

{
my $mac2=shift();
my $mac3=$mac2.'.world';
print $mac3;
print "\n";

}

Jul 12, 2010, 11:17 PM

gpta_varun

Novice (24 posts)

Jul 12, 2010, 11:17 PM

Post #2 of 15

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Re: [gpta_varun] Interesting Concatenation Problem - Require Help In reply to

Slight Change in the code

#!/usr/bin/perl

main();

sub main () {

my %config_hash=();
my @machines=();
my $i=0;
open(CONFIG, "<config_details.cfg") || die "I/O Success - Cannot process get_max_ri.sql file";

while (<CONFIG>)
{
my @config_line=split(/=/,$_);
print "$config_line[0]\n";
$config_hash{$config_line[0]}=$config_line[1];
}

@machines=split(/,/,$config_hash{"MACHINE NAMES"});
my $NUM_MACHINES=@machines;

for ($i=0;$i<=$NUM_MACHINES;$i++)
{
chomp($machines[$i]);
sub_main($i+1,$machines[$i]);
}

}

sub sub_main()

{
my $A=shift();
my $mac2=shift();
my $mac3=$mac2.'.world';
print $mac3;
print "\n";

}

Jul 12, 2010, 11:58 PM

Andy

Veteran / Moderator (18441 posts)

Jul 12, 2010, 11:58 PM

Post #3 of 15

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Re: [gpta_varun] Interesting Concatenation Problem - Require Help In reply to

So you are trying to add ".world" to the end of the string, or just "world"?

You also dont give us an example of whats being outputted, appart from saying its "weird" Wink

Cheers

Andy (mod)
andy@ultranerds.co.uk

Jul 13, 2010, 12:14 AM

gpta_varun

Novice (24 posts)

Jul 13, 2010, 12:14 AM

Post #4 of 15

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Re: [Andy] Interesting Concatenation Problem - Require Help In reply to

Want to print "XYZ.world" .
I am just getting ".world" as the output :(

Thanks

Jul 13, 2010, 12:30 AM

Andy

Veteran / Moderator (18441 posts)

Jul 13, 2010, 12:30 AM

Post #5 of 15

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Re: [gpta_varun] Interesting Concatenation Problem - Require Help In reply to

Sounds more like the value isn't being passed in. Do a couple of tests:

Code:
@machines=split(/,/,$config_hash{"MACHINE NAMES"}); 
my $NUM_MACHINES=@machines; 

use Data::Dumper; 
print "Dump of matching: " . Dumper(@machines);

for ($i=0;$i<=$NUM_MACHINES;$i++)

..and:

Code:
sub sub_main { 
   my ($A,$mac2) = @_; 

  my $mac3=$mac2.'.world'; 
  print $mac3; 
  print "\n"; 
}

Basically, check to see if what you are execting to get through, actually is.

Cheers

Andy (mod)
andy@ultranerds.co.uk

Jul 13, 2010, 1:11 AM

gpta_varun

Novice (24 posts)

Jul 13, 2010, 1:11 AM

Post #6 of 15

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Re: [Andy] Interesting Concatenation Problem - Require Help In reply to

Many Thanks for the reply Andy

I guess , i have got the problem ( not the solution though !)

My config file is
-------------------------
MACHINE NAMES=P1,P2

The result of Data Dump was :
Dump of matching: $VAR1 = 'P1';
$VAR2 = 'P2
';

As a result , while P1.world got printed correctly , P2.world did not!

For removing the new line feed , I tries chomping the array @machines , but it did not solve the problem

--varun

Jul 13, 2010, 1:13 AM

Andy

Veteran / Moderator (18441 posts)

Jul 13, 2010, 1:13 AM

Post #7 of 15

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Re: [gpta_varun] Interesting Concatenation Problem - Require Help In reply to

Before:

my @config_line=split(/=/,$_);

Try doing:

chomp;

This should get rid of the newline bit.

Cheers

Andy (mod)
andy@ultranerds.co.uk

Jul 13, 2010, 1:34 AM

gpta_varun

Novice (24 posts)

Jul 13, 2010, 1:34 AM

Post #8 of 15

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Re: [Andy] Interesting Concatenation Problem - Require Help In reply to

Still no success :(

Jul 13, 2010, 1:39 AM

Andy

Veteran / Moderator (18441 posts)

Jul 13, 2010, 1:39 AM

Post #9 of 15

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Re: [gpta_varun] Interesting Concatenation Problem - Require Help In reply to

What does the code look like now?

Cheers

Andy (mod)
andy@ultranerds.co.uk

Jul 13, 2010, 1:44 AM

gpta_varun

Novice (24 posts)

Jul 13, 2010, 1:44 AM

Post #10 of 15

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Re: [Andy] Interesting Concatenation Problem - Require Help In reply to

Code:
#!/usr/bin/perl 
use Data::Dumper; 

main(); 

sub main () { 

my %config_hash=(); 
  my @machines=(); 
  my $i=0; 
  open(CONFIG, "<config_details.cfg") || die "I/O Success - Cannot process get_max_ri.sql file"; 

  while (<CONFIG>) 
  { 
  my @config_line=split(/=/,$_); 
  chomp; 
  print "$config_line[0]\n"; 
  $config_hash{$config_line[0]}=$config_line[1]; 
  } 


  @machines=split(/,/,$config_hash{"MACHINE NAMES"}); 
  my $NUM_MACHINES=@machines; 
  print "Dump of matching: " . Dumper(@machines). "\n";  

  for ($i=0;$i<=$NUM_MACHINES;$i++) 
  { 
    chomp($machines[$i]); 
    sub_main($i+1,$machines[$i]); 
  } 

} 


sub sub_main() 

{ 
my $A=shift(); 
my $mac2=shift(); 

print "$mac2\n"; 
my $mac3=$mac2.'.world'; 
print $mac3; 
print "\n"; 

}

Quote:

Output

G> perl test.pl
MACHINE NAMES
Dump of matching: $VAR1 = 'P1';
$VAR2 = 'P2
';

P1
P1.world
P2
.world

.world

Jul 13, 2010, 1:47 AM

Andy

Veteran / Moderator (18441 posts)

Jul 13, 2010, 1:47 AM

Post #11 of 15

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Re: [gpta_varun] Interesting Concatenation Problem - Require Help In reply to

I said *before* that line Tongue

So instead of:

Code:
my @config_line=split(/=/,$_); 
chomp;

Try:

Code:
chomp;  
my @config_line=split(/=/,$_);

Basically, you need to get rid of the newline bit *before* you split it into the array Smile

Cheers

Andy (mod)
andy@ultranerds.co.uk

Jul 13, 2010, 2:05 AM

gpta_varun

Novice (24 posts)

Jul 13, 2010, 2:05 AM

Post #12 of 15

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Re: [Andy] Interesting Concatenation Problem - Require Help In reply to

Quote:

OUTPUT :( :( :( Angelic

G> perl test.pl
MACHINE NAMES
Dump of matching: $VAR1 = 'P1';
';AR2 = 'P2

P1
P1.world
P2
.world

.world

Jul 13, 2010, 2:07 AM

Andy

Veteran / Moderator (18441 posts)

Jul 13, 2010, 2:07 AM

Post #13 of 15

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Re: [gpta_varun] Interesting Concatenation Problem - Require Help In reply to

MM, instead of this:

Code:
chomp; 
my @config_line=split(/=/,$_);

Try:

Code:
$_ =~ s/[\r\n]//sg; 
my @config_line=split(/=/,$_);

Any difference?

Andy (mod)
andy@ultranerds.co.uk

Jul 13, 2010, 3:09 AM

gpta_varun

Novice (24 posts)

Jul 13, 2010, 3:09 AM

Post #14 of 15

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Re: [Andy] Interesting Concatenation Problem - Require Help In reply to

Thanks Andy !

Your suggestion worked !

Thanks again !

(Looking forward to bother you again some time later Smile

)

Jul 13, 2010, 3:15 AM

Andy

Veteran / Moderator (18441 posts)

Jul 13, 2010, 3:15 AM

Post #15 of 15

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Re: [gpta_varun] Interesting Concatenation Problem - Require Help In reply to

Cool, glad to hear it :)

Cheers

Andy (mod)
andy@ultranerds.co.uk