help with (what I consider) a strange problem

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

Fellow monks,
I am using Text::Bastardize to output user input in pig latin. But, I am encountering a problem
When I assign `<>' to a scalar, and assign the scalar to `$_', it works fine. but when I `chomp' <>, it will not work.
Sample code:

#!/usr/bin/perl -w

use strict;
use Text::Bastardize;

my $line = <>;
$_ = $line;
my $latin = Text::Bastardize->new();
$latin->charge($_);
print $latin->pig(),"\n"
[download]

That code works; but outputs with an appended newline.

When I use:

#!/usr/bin/perl -w

use strict;
use Text::Bastardize;

my $line = <>;
$_ = chomp($line);
my $latin = Text::Bastardize->new();
$latin->charge($_);
print $latin->pig(),"\n"
[download]

It doesn't output anything. I do not know whether I am making a basic error, or if Text::Bastardize's `charge' doesn't like the use of chomp for some reason

Please help :)

Comment on help with (what I consider) a strange problem Select or Download Code

Replies are listed 'Best First'.
Re: help with (what I consider) a strange problem by sachmet (Scribe) on Mar 19, 2001 at 07:22 UTC
`perldoc -f chomp` should tell you that chomp returns the total number of characters chomped from its arguments. So in essense, you're trying to piglatinize "1". Try changing `$latin->charge($_)` to `$latin->charge($line)`. As an aside, you shouldn't assign to $_. You can do Bad Things(tm) like that if you're not careful.	[reply] [d/l] [select]
Re: help with (what I consider) a strange problem by danger (Priest) on Mar 19, 2001 at 07:16 UTC
You are assigning the return value of chomp() to $_ ... and chomp() returns whatever it chomped off the end of the string, not the chomped string. updateMy bad ... chomp() returns the number of characters chomped off --- it seems Text::Bastardize has a problem with digits and hangs, at least that's what I get with this example: `#!/usr/bin/perl -w use strict; use Text::Bastardize; my $latin = Text::Bastardize->new(); $latin->charge('blah 10 '); print $latin->pig(),"\n"` [download] seems like a bug in Bastardize to me.	[reply] [d/l]
Re: Re: help with (what I consider) a strange problem by sachmet (Scribe) on Mar 19, 2001 at 07:26 UTC
Nope... chomp returns number of chars chopped. So: `$t = "t\n"; $num = chomp($t); print "$num"` prints "1", whereas: `$t = "t"; $num = chomp($t); print "$num"` prints "", whereas: `@t = ("t\n","u\n","v","w\n"); $num = chomp(@t); print "$num";` [download] prints "3". (edited: error in my code fixed)	[reply] [d/l] [select]
Re: help with (what I consider) a strange problem by dusk (Friar) on Mar 19, 2001 at 08:06 UTC
Thank you all for your help. I apologize for neglecting to use perldoc My code is now: `#!/usr/bin/perl -w use strict; use Text::Bastardize; chomp(my $line = <>); my $latin = Text::Bastardize->new(); $latin->charge($line); print $latin->pig(),"\n"` [download] Which works perfectly :) update: removed unecessary `$_' assignment. Thanks danger :)	[reply] [d/l]
Re: Re: help with (what I consider) a strange problem by chipmunk (Parson) on Mar 19, 2001 at 08:17 UTC
I can't figure out why that code even compiles. Assigning to chomp should result in the following error: `Can't modify scalar safe chop in scalar assignment...` But, this error doesn't occur when assigning to chomp if the argument to chomp is an assignment from a filehandle read. Some sort of obscure parsing bug... Here's what your code should look like: `#!/usr/bin/perl -w use strict; use Text::Bastardize; chomp(my $line = <>); my $latin = Text::Bastardize->new(); $latin->charge($line); print $latin->pig(),"\n";` [download]	[reply] [d/l] [select]


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