gon770 has asked for the wisdom of the Perl Monks concerning the following question:

Hello, PerlMonks.

I am having trouble with new lines (\n). It seems like everything within scalar will print new line. For instance,

$_ and $fa
$fb
$fc

But, I want it to be $_ $fa $fb $fc in same line.
Should I try different function? Or there is an optional augument for scalar function? Thank you 

while(<$fi>){
        chomp;
    print CSV $_, scalar <$fa>, scalar <$fb>, scalar <$fc>;
}

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Replies are listed 'Best First'.
Re: Scalar function
by MidLifeXis (Monsignor) on Sep 07, 2012 at 17:11 UTC

    If $fa, $fb, and $fc are file handles, then 

    print CSV $_, scalar <$fa>, scalar <$fb>, scalar <$fc>;

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    is doing the equivalent of 
      my $line_a = <$fa>;
  my $line_b = <$fb>;
  my $line_c = <$fc>;

  print CSV $_, $line_a, $line_b, $line_c;

    [download]
    Note that there is no chomp on the reads from the three files.

    --MidLifeXis

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Re: Scalar function
by johngg (Canon) on Sep 07, 2012 at 22:45 UTC

    As MidLifeXis points out, you need to chomp your newlines.

    $ perl -E '
> open my $fa, q{<}, \ <<EOF1 or die $!;
> file A line 1
> file A line 2
> EOF1
> 
> open my $fb, q{<}, \ <<EOF2 or die $!;
> file B line 1
> file B line 2
> EOF2
> 
> say join q{,},
>    map { chomp; $_ } scalar <$fa>, scalar <$fb>;'
file A line 1,file B line 1
$

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    I hope this is helpful.

    Update: A more complete example putting the $fa, $fb and $fc filehandles in an array and showing how you might cope if they contain fewer lines than $fi using eof.

    $ perl -Mstrict -Mwarnings -E '
> open my $fi, q{<}, \ <<EOFi or die $!;
> File I Line 1
> File I Line 2
> File I line 3
> EOFi
> 
> open my $fa, q{<}, \ <<EOFa or die $!;
> File A Line 1
> File A Line 2
> EOFa
> 
> open my $fb, q{<}, \ <<EOFb or die $!;
> File B Line 1
> File B Line 2
> File B Line 3
> EOFb
> 
> open my $fc, q{<}, \ <<EOFc or die $!;
> File C Line 1
> File C Line 2
> File C Line 3
> File C Line 4
> EOFc
> 
> my @slaveFHs = ( $fa, $fb, $fc );
> while ( <$fi> )
> {
>     chomp;
>     say join q{,}, $_,
>        map { chomp; $_ }
>        map { eof $_ ? q{--eof--} : scalar <$_> }
>        @slaveFHs;
> }'
File I Line 1,File A Line 1,File B Line 1,File C Line 1
File I Line 2,File A Line 2,File B Line 2,File C Line 2
File I line 3,--eof--,File B Line 3,File C Line 3

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    Cheers,

    JohnGG

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Re: Scalar function
by philiprbrenan (Monk) on Sep 07, 2012 at 16:57 UTC
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