«

There must be something that I have ignored in PERL.

To split a string with delimiter "|", sometimes, I need to give "\",
sometimes it works for "\\" only.

Here are the details.

The String is " 0000|Null".

And the ways I have tried to do split are:
1. my @columns = split('\|', $String);
2. my ( $proj, $desc) = split('\|', $String);
3. my ( $proj, $desc) = split('\\|', $String);

Case 1 and Case 3 are good. But Case 2 failed, both $proj and $desc
receive an empty string .

What was wrong with case 2 , I thought if Case 1 works, Case2 should
be working also, Right ? I am using perl 5.6.1 on linux box.



Thanks a lot for the tips.


John.

On Feb 22, 11:01 am, John <chunj...@gmail.com> wrote:
> There must be something that I have ignored in PERL.
>
> To split a string with delimiter "|", sometimes, I need to give "\",
> sometimes it works for "\\" only.
>
> Here are the details.
>
> The String is " 0000|Null".
>
> And the ways I have tried to do split are:
> 1. my @columns = split('\|', $String);
> 2. my ( $proj, $desc) = split('\|', $String);
> 3. my ( $proj, $desc) = split('\\|', $String);
>
> Case 1 and Case 3 are good. But Case 2 failed, both $proj and $desc
> receive an empty string .
>
> What was wrong with case 2 , I thought if Case 1 works, Case2 should
> be working also, Right ? I am using perl 5.6.1 on linux box.
>

case 2 works as is. Is it possible you meant:
split( "\|", $String ) ...?

In that case, double-quotish interpolation causes
your split regex to be just '|':

# perl -MO=Deparse,-p -e 'split "\|"," 0000|Null"'
split(/|/, ' 0000|Null', 0);
-e syntax OK

Then, you have the alternation meta character
alone with empty alternatives on either side
which'll match the 1st 2 characters encountered:

$proj=' ' $desc='0'

Is it possible you had 2 leading blanks in
string which "looked" like 2 empty strings for
$proj and $desc...

--
Charles DeRykus

Quoth John <>:
>
> There must be something that I have ignored in PERL.
>
> To split a string with delimiter "|", sometimes, I need to give "\",
> sometimes it works for "\\" only.
>
> Here are the details.
>
> The String is " 0000|Null".
>
> And the ways I have tried to do split are:
> 1. my @columns = split('\|', $String);
> 2. my ( $proj, $desc) = split('\|', $String);

The first argument to split is a regex (with the special exception of
' '). Don't pass something that looks like a string, you'll just confuse
yourself.

my (@proj, $desc) = split(/\|/, $String);

Ben

On Feb 22, 11:56*am, "comp.llang.perl.moderated" <c...@blv-
sam-01.ca.boeing.com> wrote:
> On Feb 22, 11:01 am, John <chunj...@gmail.com> wrote:
>
>
>
>
>
> > There must be something that I have ignored in PERL.
>
> > To split a string with delimiter "|", sometimes, I need to give "\",
> > sometimes it works for "\\" only.
>
> > Here are the details.
>
> > The String is " 0000|Null".
>
> > And the ways I have tried to do split are:
> > 1. my @columns *= split('\|', $String);
> > 2. my ( $proj, $desc) = split('\|', $String);
> > 3. my ( $proj, $desc) = split('\\|', $String);
>
> > Case 1 and Case 3 are good. But Case 2 failed, both $proj and $desc
> > receive an empty string .
>
> > What was wrong with case 2 , I thought if Case 1 works, Case2 should
> > be working also, Right ? *I am using perl 5.6.1 on linux box.
>
> case 2 works as is. *Is it possible you meant:
> split( "\|", $String ) ...?
>
> In that case, double-quotish interpolation causes
> your split regex to be just '|':
>
> # perl -MO=Deparse,-p -e 'split "\|"," 0000|Null"'
> split(/|/, ' 0000|Null', 0);
> -e syntax OK
>
> Then, you have the alternation meta character
> alone with empty alternatives on either side
> which'll match the 1st 2 characters encountered:
>
> * $proj=' ' *$desc='0'
>
> Is it possible you had 2 leading blanks in
> string which "looked" like 2 empty strings for
> $proj and $desc...
>
> --
> Charles DeRykus- Hide quoted text -
>
> - Show quoted text -

I do not have any leading blanks in this String.

-John

John <> wrote:
>
>
>There must be something that I have ignored in PERL.
>
>To split a string with delimiter "|", sometimes, I need to give "\",
>sometimes it works for "\\" only.
>
>Here are the details.
>
>The String is " 0000|Null".
>
>And the ways I have tried to do split are:
>1. my @columns = split('\|', $String);
>2. my ( $proj, $desc) = split('\|', $String);
>3. my ( $proj, $desc) = split('\\|', $String);
>
>Case 1 and Case 3 are good. But Case 2 failed, both $proj and $desc
>receive an empty string .

I cannot reproduce your results:

C:\tmp>type t.pl
use strict; use warnings;
my $String = " 0000|Null";
my @columns = split('\|', $String);
print "@columns\n";
my ( $proj, $desc) = split('\|', $String);
print $proj, ' ', $desc, "\n";
( $proj, $desc) = split('\\|', $String);
print $proj, ' ', $desc , "\n";

C:\tmp>t.pl
0000 Null
0000 Null
0000 Null

Each of versions produces the same result as the others.

jue

On Feb 22, 12:34 pm, John <chunj...@gmail.com> wrote:
> On Feb 22, 11:56 am, "comp.llang.perl.moderated" <c...@blv-
>
>
>
> sam-01.ca.boeing.com> wrote:
> > On Feb 22, 11:01 am, John <chunj...@gmail.com> wrote:
>
> > > There must be something that I have ignored in PERL.
>
> > > To split a string with delimiter "|", sometimes, I need to give "\",
> > > sometimes it works for "\\" only.
>
> > > Here are the details.
>
> > > The String is " 0000|Null".
>
> > > And the ways I have tried to do split are:
> > > 1. my @columns = split('\|', $String);
> > > 2. my ( $proj, $desc) = split('\|', $String);
> > > 3. my ( $proj, $desc) = split('\\|', $String);
>
> > > Case 1 and Case 3 are good. But Case 2 failed, both $proj and $desc
> > > receive an empty string .
>
> > > What was wrong with case 2 , I thought if Case 1 works, Case2 should
> > > be working also, Right ? I am using perl 5.6.1 on linux box.
>
> > case 2 works as is. Is it possible you meant:
> > split( "\|", $String ) ...?
>
> > In that case, double-quotish interpolation causes
> > your split regex to be just '|':
>
> > # perl -MO=Deparse,-p -e 'split "\|"," 0000|Null"'
> > split(/|/, ' 0000|Null', 0);
> > -e syntax OK
>
> > Then, you have the alternation meta character
> > alone with empty alternatives on either side
> > which'll match the 1st 2 characters encountered:
>
> > $proj=' ' $desc='0'
>
> > Is it possible you had 2 leading blanks in
> > string which "looked" like 2 empty strings for
> > $proj and $desc...
>
> > --
> > Charles DeRykus- Hide quoted text -
>
> > - Show quoted text -
>
> I do not have any leading blanks in this String.
>

Hm, the original post does however:

> "The String is " 0000|Null".

--
Charles DeRykus