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perl string match issue

Hi every one,

Code:

#!/usr/bin/perl 



open FILE, "<", "test-last" or die $!;





while (<FILE>) {



$test= $_;  //current line become $test



@names=qw( one two three four );    //aray to hold few values



foreach  $names(@names){

print " $test";  print "$names";  // now here it matches!! i mean string from file and from //aray



if($test eq $names){



print "match found \n";  //doenst print a thing



}

test-last

Code:

five

six

two

seven

See "two" should print "match found" but it doesn't.

Any ideas?

Thanks

You left out two ending brackets when you pasted your code btw. :)

If you put a

Code:

print "Length of test is " . length($test) . "\n";

in your code you'll notice that it's one character longer than the actual length of your $test variable that you're pulling from the file. You're pulling a newline character. After your foreach line add a

Code:

chomp($test);

and it should work fine.

That's because the lines from the file have a newline at the end, whereas the ones in your array do not. Use chomp to remove it:

Code:

#!/usr/bin/perl -w 

use strict; 



my @names=qw( one two three four );    # no need to redeclare this each time in the loop!



while (<DATA>) {

        my $test=$_;

        chomp $test;        # removes newline

        foreach  $name(@names){

                print "\"$test\" \"$name\"\n"; # using escaped quotes you could have seen this  

                if($test eq $name) {print "MATCH FOUND!\n"}

        }

}



__DATA__

five

six

two

You can read in data from the end of a script this way the same as if it were in a file. Using the escaped quotes in your original version you would have seen this:

"five
" "one"
"five
" "two"

"perlmonks" is a good and very active forum for perl help.

ps. why did you use c-style comments?

Quote:

Originally Posted by mk27 (Post 3399033)

ps. why did you use c-style comments?

I am deeply in love with C :(, . the first language I learned second would be perl.
I love playing on hardware level with C. Its awesome

Thank you very much both of you,
mk27 thanks for pointing out loop thingie.

Good time to ask an old question

Code:

my @names=qw( one two three four );    # no need to redeclare this each time in the loop!



while (<DATA>) {

        my $test=$_;

why did you use "my" before declaring array and variable ?

Thanks

Quote:

Originally Posted by knockout_artist (Post 3399121)

Thank you very much both of you,
mk27 thanks for pointing out loop thingie.

Yeah, sorry about that... didn't mean to put it in the loop there.

@knockout-artist; ALL perl programs should start with

Code:

#!/usr/bin/perl -w 

use strict;

which will warn you about syntax errors and dodgy code usage. Never code without them :)
An alternative to '-w' is 'use warnings;'

Also, if you want to do a test compile without running the prog, use

perl -wc prog.pl

If you 'use strict;' then you have to declare your vars using 'my', which restricts their scope to the current block (usually current subroutine). IOW, avoid globals as much as possible.
Think C (also my main lang prev to Perl).
:)

Good Perl links:
http://perldoc.perl.org/
http://www.perlmonks.org/?node=Tutorials

Code:

 

#!/usr/bin/perl 

use strict;



my $flag =0 ;      #used to flags

my $flag2 =0;

my @names=qw(  ); #empty array

my $i=0;          # mostly for debugging

my $j=0;          #same as above 

my $test;          #hold value from __DATA__



while(<DATA>)    #read all 4 valuse from  DATA

{

print "$flag Flag at start\n";  #debugging

my $test=$_;

chomp($test);



if ($j==0 ){                  #add first value in the array so in next loop it would have some thing to look at

print "push $test into names array\n";

  push (@names, "$test" );

  }

print "name from DATA $test\n";    #debug  print value read from data



foreach my $names(@names){          #inner loop  for @names array

print " Test==$test Names==$names \n";    #debug

if($test eq $names){                      #make sure that if it already exist

$flag = 2;                                  #playing with those to flags



$flag2 =1;



}else{



$flag =0 ;

}

if ($flag != 2 ){



$flag = 0;



}



}

print " test = $test  flag = $flag  \n";

$j++;

if($flag ==0){

push (@names, "$test" );      #Tried differnt flag



}

print "flag2 $flag2\n";

}

$flag2 =0;

print "@names\n";



__DATA__

one

one

three

one

What I need is out put
[qoute]one three[/quote]

what I get is

Quote:

one three one

output ::

Code:

  ./last-log2.pl 

0 Flag at start

push one into names array

name from DATA one

 Test==one Names==one 

 test = one  flag = 2  

flag2 1

2 Flag at start

name from DATA one

 Test==one Names==one 

 test = one  flag = 2  

flag2 1

2 Flag at start

name from DATA three

 Test==three Names==one 

 test = three  flag = 0  

flag2 1

0 Flag at start

name from DATA one

 Test==one Names==one 

 Test==one Names==three 

 test = one  flag = 0  

flag2 1

one three one  ## print whats inside the array

Any ideas?
Thanks!

BTW

I was able to resolve it.
I will post the code tomorrow.

Thank you every one. :-)

Don't forget the -w switch (or 'use warnings').

I'd also change

while(<DATA>)

to

while( defined($test = <DATA>) )

removing need for

my $test=$_;

Try indenting your code as well, its easier to read...

Seconded on warnings & strict.
My Perl places will tell you to put those in and run your code again before bothering to help... although I don't think they would've helped here.