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


Hi..

Could somebody help me how to remove trailing space from my data ?.

This is an example of the input data:- 
0001AE~060327733999           ~60122115338           ~-0800N4A39FA69~-
+0800N4A39FA71~00~00~     ~
         ~NOKGLB                        ~                    ~        
+            ~               ~0020~

[download]

Actually, after "~0020~", its will be a lots of spaces. How could i removed that?

Thank you,

Replies are listed 'Best First'.
Re: How to remove trailing space ?
by ikegami (Patriarch) on Jun 22, 2009 at 04:42 UTC
    Just spaces: 
    $line =~ s/ +$//;

    [download]
    The following will remove some other forms of whitespace too: 
    $line =~ s/\s+$//;

    [download]
[reply]
[d/l]
[select]
Re: How to remove trailing space ?
by Anonymous Monk on Jun 22, 2009 at 02:59 UTC
[reply]
Re: How to remove trailing space ?
by captain.moor (Novice) on Jun 22, 2009 at 04:32 UTC
    You can read up on chomp() and failing that a simple regex of s|\n||g might work.
[reply]
Re: How to remove trailing space ?
by perliff (Monk) on Jun 22, 2009 at 13:19 UTC
    since this is such a commonly done affair... its best to define small functions, say trim (to remove leading and trailing whitespace), trimstart (to remove leading whitespace only ), and trimend (to remove trailing whitespace only), and use them again and again. I have had to do this quite often and find these functions quite useful...Here are the functions, as I use them, as part of a module where I keep my commonly used functions. 
    use strict;
use Data::Dumper;

my $line1 = "  first ";
my $line2 = "  second ";

print "\nlines to be trimmed...\n";
print Dumper $line1;
print Dumper $line2;

$line1 = trim ($line1);
$line2 = trim ($line2);
print "\nafter trimming start and end both...\n";
print Dumper $line1;
print Dumper $line2;

# in case u have an array.. you can use the map function
# say  
my @array;

# and stuff with spaces at the beginning or end or both
$line1 = "  first ";
$line2 = "  second ";

print "\nlines to be trimmed...\n";
print Dumper $line1;
print Dumper $line2;

push (@array,$line1);
push (@array,$line2);

print "\narray to be trimmed...\n";
print Dumper @array;
my @array2 = map { trim ($_) } @array;
print "\ntrimmed array\n";
print Dumper @array2;


# using trimstart and trimend
$line1 = "  first ";
$line2 = "  second ";
print "\nlines to be trimmed...\n";
print Dumper $line1;
print Dumper $line2;


$line1 = trimstart ($line1);
$line2 = trimend ($line2);

print "\ntrimming the start using trimstart...\n";
print Dumper $line1;
print "\ntrimming the end using trimend...\n";
print Dumper $line2;


sub trim {

 # remove both leading and trailing whitespace
 my $line =  shift;
 $line=~s/^\s+|\s+$//g;
 return $line;

}

sub trimstart {

 # remove leading whitespace
 my $line =  shift;
 $line=~s/^\s+//g;
 return $line;

}

sub trimend {

 # remove trailing whitespace
 my $line =  shift;
 $line=~s/\s+$//g;
 return $line;

}

    [download]

    perliff

    ----------------------

    -with perl on my side

[reply]
[d/l]
[reply]
        cool...now why didn't I look for it before?.. oh well... I guess once I'd coded these trim functions I never looked for a module to do this... as I was already importing these from my own module all the time anyway...

        perliff

        ----------------------

        -with perl on my side

[reply]

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