Re: formline, undefined format STDOUT

formline is low level function. As shown in perlformat, you have to use it with $^A (which you could also localize):

formline( "@<< @<< @<<", '1', '2', '2' );
print "$^A\n";
[download]

or specify an empty format before:

format =
.
formline( "@<< @<< @<<", '1', '2', '2' );
write;
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Use a higher level format:

format =
@<< @<< @<<
1,  2,  2
.
write;
[download]

Or, switch to plain sprintf:

say join ' ', map sprintf('%-3d', $_), 1, 2, 2;
[download]

لսႽ† ᥲᥒ⚪⟊Ⴙᘓᖇ Ꮅᘓᖇ⎱ Ⴙᥲ𝇋ƙᘓᖇ

Comment on Re: formline, undefined format STDOUT Select or Download Code

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Re^2: formline, undefined format STDOUT by Anonymous Monk on Apr 20, 2015 at 14:47 UTC
lets say there are two fields, one of them is long and other one is small. Whats the ways to print all the contents `$l = "This is long string" ; $s = "s"; format STDOUT = ~~ @<<< @< $l, $s .` [download] above is not working.	[reply] [d/l]
Re^3: formline, undefined format STDOUT by choroba (Cardinal) on Apr 20, 2015 at 15:17 UTC
As documented in perlform, `~~` should be used for changing values that finally become undefined. `#!/usr/bin/perl use warnings; use strict; my @l = ('This is long string', 'Another long one'); my @s = ('s', 'S'); format = ~~ @<<<<<<<<<<<<<<<<<<< @< shift @l, shift @s . write;` [download] It's time you read the documentation again. I've never used formats in Perl, and I hope I never will; but I was able to put this together in one minute. لսႽ† ᥲᥒ⚪⟊Ⴙᘓᖇ Ꮅᘓᖇ⎱ Ⴙᥲ𝇋ƙᘓᖇ	[reply] [d/l] [select]
Re^4: formline, undefined format STDOUT by Anonymous Monk on Apr 20, 2015 at 17:23 UTC
Thnx for your help, this is what I was looking for : `#!/usr/bin/perl use warnings; use strict; my @row; my @f_map = ('f1', 'f2'); my $f = "format = \n" . ('^' . '<' x 15 . '\|') x scalar(@f_map) . "\n" . '@row' . "\n" . ('^' . '<' x 15 . '\|') x scalar(@f_map) . "~~\n" . '@row' . "\n" . ".\n"; eval($f); # @row = ('blah1' x 10, 'blah2' x 10); write;` [download] output : `blah1blah1blah1b\|blah2blah2blah2b\| lah1blah1blah1bl\|lah2blah2blah2bl\| ah1blah1blah1bla\|ah2blah2blah2bla\| h1 \|h2 \|` [download]	[reply] [d/l] [select]