nested Perl index gives error

quadmore · 02-06-2007, 03:33 PM

Hello,

I am using a line of perl code in a bash script to search for a substring in a string.

MYSUBSTRING="TOP"
# I tried this line:
# POSITION=$(perl -e "print index($FILE_ATTENTE,$MYSUBSTRING);")
# and I also tried:
# POSITION=`perl -e "print index(${FILE_ATTENTE},${MYSUBSTRING});"`
# but with both previous I get the same exact result as with:
POSITION=`perl -e 'print index('$MYSTRING','$MYSUBSTRING');'`
echo ""
if [ $POSITION -gt 0 ]
then
# ... additiona code
fi

It works fine, giving "-1" when not found and an integer if found. Normal result:


The script fails for two strings, however.

The problem strings as they show up are:


<font color="red">SYSTEM.JMS.D.0.MA</font><br>


I get no "-1" value. Plus, I get the following complaints:

Bareword found where operator expected at -e line 1, near "0.MA"
(Missing operator before MA?)
syntax error at -e line 1, near "0.MA"
Execution of -e aborted due to compilation errors.
./getGFAQueues.sh: line 114: [: -gt: unary operator expected
Bareword found where operator expected at -e line 1, near "0.MP"
(Missing operator before MP?)
syntax error at -e line 1, near "0.MP"
Execution of -e aborted due to compilation errors.
./getGFAQueues.sh: line 114: [: -gt: unary operator expected

Don't understand what is causing the error. How do I fix?

Thanks in advance!

matthewg42 · 02-06-2007, 04:13 PM

Please post scripts and output in [code] tags to improve readability.

First thing: Use of ! in double quotes: bash will attempt to expand this to an event, so I would expect to a message something like:

Code:

bash: !--": event not found

Use single quotes to prevent this:

Code:

echo '<!--'

Second thing: what are the values of MYSTRING and MYSUBSTRING? After the perl line, it would help to add an echo of these values to be sure what is going on. For sure the problem is something to do with quotes. Here's how I'd do it in a way which reduces the mess of quotes:

Code:

MYSTRING="J. R. Bob Dobbs"
MYSUBSTRING="Bob"
POSITION=$(perl <<EOP
  print index("$MYSTRING", "$MYSUBSTRING") . "\n";
EOP)
echo "MYSTRING      = $MYSTRING"
echo "MYSUBSTRING   = $MYSUBSTRING"
echo "POSITION      = $POSITION"

See if that helps.

quadmore · 02-07-2007, 09:58 AM

Hello,

The perl index function returns a null or blank on the following string values:

SYSTEM.JMS.D..MA
SYSTEM.JMS.D..MP

I am guessing it must be the concatenation operator (dot). All three of the following give the same results:
POSITION=`perl -e "print index(${MYSTRING},${MYSUBSTRING});"`
POSITION=`perl -e 'print index('$MYSTRING','$MYSUBSTRING');'`
POSITION=$(perl -e "print index($MYSTRING,$MYSUBSTRING);")

I guess I am now looking for a Perl funtion to indicate I need to ignore dots, which will wrap the index function.

Can someone please confirm?

Thanks!

matthewg42 · 02-07-2007, 11:06 AM

what are the values of MYSTRING and MYSUBSTRING when this happens?

quadmore · 02-07-2007, 11:11 AM

String = System.jms.d..ma
Mysubstring = Top

quadmore · 02-07-2007, 11:12 AM

previous post is not displaying properly, everything is uppercase