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Issues with an exact match using regex in perl!

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Top Forums Shell Programming and Scripting Issues with an exact match using regex in perl!
# 1  
Old 06-16-2010
Issues with an exact match using regex in perl!
Hello Guys,

I am trying to make an exact match for an email address entered as an argument, using perl, however, it's not working if I put a "$" in the email address. See the below outputs,

Correct Match :

Code:
bash-2.03$ echo sandy@test.com | perl -wln -e 'print if /(^[a-zA-Z0-9\w+\.\_\-]*\@test.com$)/i'
sandy@test.com

Incorrect Match :

Code:
bash-2.03$ echo $sandy@test.com | perl -wln -e 'print if /(^[a-zA-Z0-9\w+\.\_\-]*\@test.com$)/i'
@test.com

Ideally it should not give any output for the second command. Any help in this regard would be greatly appreciated.

---------- Post updated at 05:28 AM ---------- Previous update was at 05:25 AM ----------

See the below entry,

Code:
bash-2.03$ echo SInGH$$$$sand@TEST.com
SInGH78497849sand@TEST.com

Last edited by pludi; 06-16-2010 at 06:59 AM.. Reason: code tags, please...
# 2  
Old 06-16-2010
How about this:
Code:
perl -wln -e 'print if /(^[a-zA-Z0-9\w+\._-]+\@test.com$)/i'

It is best to put "" around a variable reference to avoid interpretation by the shell, but in the case of a string the $ characters would still be interpreted so you have to use single quotes.
Code:
echo 'SInGH$$$$sand@TEST.com'

( $sandy got interpretated as a variable which is empty )
# 3  
Old 06-16-2010
Further to Scrutinizer's points, you may want to simplify the regex. The backreference is not used, so the round brackets may be discarded. "\w" takes care of "a-zA-Z0-9_". The dot (".") loses its special meaning inside a character class. The dash ("-") need not be escaped inside the brackets, rather, putting it at the end is enough to avoid it from being expressed as a range character. And finally, add the "$" inside the character class if you want to match it.

Here's the updated regex -

Code:
$
$
$ echo 'sandy@TEST.com' | perl -wlne 'print if /^[\w.\$-]+\@test.com$/i'
sandy@TEST.com
$
$ echo '$sandy@TEST.com' | perl -wlne 'print if /^[\w.\$-]+\@test.com$/i'
$sandy@TEST.com
$
$ echo 'SInGH$$$$sand@TEST.com' | perl -wlne 'print if /^[\w.\$-]+\@test.com$/i'
SInGH$$$$sand@TEST.com
$
$ echo 'Jan99Der$.Goyvaerts_burton-weiss@TEST.com' | perl -wlne 'print if /^[\w.\$-]+\@test.com$/i'
Jan99Der$.Goyvaerts_burton-weiss@TEST.com
$
$

tyler_durden
Last edited by durden_tyler; 06-16-2010 at 09:50 AM..
# 4  
Old 06-18-2010
That worked, however, now script is not working
using single quotes instead of double has worked, however, now the output of that command is not being assigned to a variable, see the below command,

Code:
ADDCHECK=`echo -n 'sandy@test.com' | perl -wln -e 'print if /(^[a-zA-Z0-9\w+\.\_\-]*\@test.com$)/i'`

Now ADDCHECK is getting null value, please help me out !!!

Moderator's Comments:
Mod Comment Please use code tags
# 5  
Old 06-18-2010
Quote:
Originally Posted by suffisandy
...
Code:
ADDCHECK=`echo -n 'sandy@test.com' | perl -wln -e 'print if /(^[a-zA-Z0-9\w+\.\_\-]*\@test.com$)/i'`

Now ADDCHECK is getting null value, please help me out !!!

...
Are you sure ? It works fine for me.

What's your shell and OS ?

Code:
$
$
$ echo $SHELL
/bin/bash
$
$
$ echo -n 'sandy@test.com' | perl -wln -e 'print if /(^[a-zA-Z0-9\w+\.\_\-]*\@test.com$)/i'
sandy@test.com
$
$
$ echo $ADDCHECK
$
$
$ ADDCHECK=`echo -n 'sandy@test.com' | perl -wln -e 'print if /(^[a-zA-Z0-9\w+\.\_\-]*\@test.com$)/i'`
$
$
$ echo $ADDCHECK
sandy@test.com
$
$

tyler_durden
# 6  
Old 06-18-2010
am using bash on solaris
Code:
bash-2.03$ uname -a
SunOS romulus 5.8 Generic_117350-62 sun4u sparc SUNW,Ultra-4



---------- Post updated at 02:48 PM ---------- Previous update was at 02:37 PM ----------

If I use double quotes, it works fine, see below

Code:
bash-2.03$ bash -x ./six.sh sandy@test.com
++ echo -n sandy@test.com
++ perl -wln -e 'print if /(^[a-zA-Z0-9\w+\.\_\-]*\@test.com$)/i'
+ ADDCHECK=sandy@test.com
+ echo sandy@test.com
sandy@test.com
bash-2.03$

If I use single quotes, than it doesnot works,

Code:
bash-2.03$ bash -x ./six.sh sandy@test.com
++ echo -n '$1'
++ perl -wln -e 'print if /(^[a-zA-Z0-9\w+\.\_\-]*\@test.com$)/i'
+ ADDCHECK=
+ echo ''

Last edited by Scott; 06-18-2010 at 03:52 PM.. Reason: Code tags, PLEASE!
# 7  
Old 06-18-2010
Can you paste the script "six.sh" (or at least the relevant part of it) over here ?

Code:
cat -n six.sh

tyler_durden
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