ActivePerl ~s/ / / and ~tr/ / / and lc() not working

[fheleno]

Hi,
I am using Activeperl 5.10.

Its replace methods or functions do not seem working.

I need to replace every uppercase letter by its corresponding lowercase.
I used $str=~ s/A-Z/a-z/; $str=lc($str); and $str=~ s/[A-Z]/[a-z]/;

Could you help, please?

thank you

Fernando

[numberwhun]

Instead of using the substitution, you want to use translate. Substitue, the way you are using it, looks for a pattern (on the left) and then replaces it with a replacement (on the right).

You want something like this:

$str=~ tr/A-Z/a-z/;
 

Also,with the lc() function, I find it better to put the output into a new variable, instead of the one you are reading from. Here is an example:

my $newstr = lc($str);
 

That should work much better for you.

Regards,

Jeff

[fheleno]

Hi Jeff,
Thank you for your answer.

I had tried your tips without success.

Probably my perl interpreter is corrupted.

I will tell you.

best regards

Fernando

[numberwhun]

Do us a favor and post your code, enclosed in code tags, and we will have a look at it and see if it works.

Regards,

Jeff

[fheleno]

Hi,
Thank you for your help.

I am using Windows7 and also tried another computer with Windows XP
getting the same result, an empty string.

Here is the code I used ( 3 options) for testing purposes:

INICIO: if (defined($_ = <STDIN>)) {$t=$_;if($_==0){exit;}}
print$t."\n";
 
#my $t1=lc($t);
 
#$t1=~ s/A-Z/a-z/g;
 
$t1=~ tr/A-Z/a-z/;
 
 
print $t1;
 
goto INICIO;
 

Thank you again and best regards

Fernando

[RonB]

EVERY Perl script you write should load the warnings and strict pragmas. If you had done so, then they would have informed you that $t1 was never defined.

use strict;
use warnings;

Don't use the goto. That's a holdover from perl 4 and nowdays is only used in very rare cases, which you will probably never come across. Instead, you should be using a while loop.

Do not put multiple statements on a single line.

You need to chomp $t

This looks like a homework assignment, so I won't provide the complete solution, but the clues I gave should help to solve the problem.

[fheleno]

Hi,
Thank you.
Your remarks helped me to find a serious error:

Using '==' instead of 'eq' stoped the script too earlier.

Thank you again,

Best regards

Fernando