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Perl Substition with multiple conditions

 
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# 1  
Old 09-25-2008
PHP Perl Substition with multiple conditions
I have a text file that contains lines similar to the following:

-----------------------------------------------------------
fall for setup

CSHRC0 'gnd';
CSHR0 'gnd';

rise for setup

rise for hold

CSHRC0 'gnd';
CSHR0 'gnd';

fall for hold
------------------------------------------------------------

I am trying to replace the gnd in between fall for setup and rise for setup with 0.75*vdd.

I tried the following:
Code:
perl -e 's/gnd/0\.75\*vdd/ if m/CSHRC0/ && /fall\ for\ setup/ .. /rise\ for\ setup/' -pi file
perl -e 's/gnd/0\.75\*vdd/ if m/CSHR0/ && /fall\ for\ setup/ .. /rise\ for\ setup/' -pi file

But these don't seem to work at all. I believe the problem is with how I am using the && operator to combine both conditions, since if I use any of those two conditions separately they would work. How can I apply multiple if conditions to the same substitution?
# 2  
Old 09-25-2008
Try parentheses.

Code:
perl -e 's/gnd/0\.75\*vdd/ if (m/CSHRC0/ && /fall\ for\ setup/ .. /rise\ for\ setup/)'

# 3  
Old 09-25-2008
I tried using () and it still didn't change anything. Is this platform dependent? I think I am using UNIX with c shell right now.
# 4  
Old 09-25-2008
Sorry for the false diagnostic; it was a shot from the hip and I should have tested before posting. The real problem is in how /x/ .. /y/ is implemented -- it will fail to see the starting condition if the /CSHRC0/ condition in front of it fails! So just reverse those conditions.

Code:
perl -pe 's/gnd/0.75*vdd/ if /fall for setup/ .. /rise for setup/ && /CSHRC?0/'

I took out some redundant backslashes, too.

Are you replacing both occurrences of gnd? Then the single condition /CSHRC?0/ should cover both of those. Take out the question mark and adapt accordingly if that was not what you meant.
Last edited by era; 09-25-2008 at 03:52 PM.. Reason: Question mark in regex to cover both gnd occurrences
# 5  
Old 09-25-2008
Thank you very much for the quick response. I tried reversing it, but somehow all the instances of gnd in the file got replaced by 0.75*vdd. So I tried Parentheses for the range condition and then it worked out fine.

Code:
perl -e 's/gnd/0\.75\*vdd/ if (/fall for setup/ .. /rise for setup/) && m/CSHRC?0/' -pi file

Thanks again for the help.
 
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