regex challenge


 
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# 1  
Old 10-01-2008
regex challenge

Here's a regex substitution operation that has stumped me with sed:

How do you convert lines like this:

Code:
first.key ?{x.y.z}
second.key ?{xa.ys.zz.s}
third.key ?{xa.k}

to:

Code:
first.key ?{x_y_z}
second.key ?{xa_ys_zz_s}
third.key ?{xa_k}


So i'm basically converting all the periods within the ?{...} structure to underscores, without changing the periods outside of this structure?
# 2  
Old 10-01-2008
if u don't mind, i can try this in awk instead of sed
Code:
awk -v FS='[}{]' '{gsub(/\./,"_",$2); print $1"{"$2"}"}' /path/of/file

# 3  
Old 10-01-2008
Code:
$ cat data
first.key ?{x.y.z}
second.key ?{xa.ys.zz.s}
third.key ?{xa.k}
$ sed -e :a -e's/\([^{][^{]*{[^.][^.]*\)\./\1_/;ta' < data
first.key ?{x_y_z}
second.key ?{xa_ys_zz_s}
third.key ?{xa_k}
$
$

This can probably be simplified; however, obvious simplifications did not seem to work. Smilie It's trickier than it looks.
# 4  
Old 10-01-2008
Quote:
Originally Posted by Perderabo
Code:
$ cat data
first.key ?{x.y.z}
second.key ?{xa.ys.zz.s}
third.key ?{xa.k}
$ sed -e :a -e's/\([^{][^{]*{[^.][^.]*\)\./\1_/;ta' < data
first.key ?{x_y_z}
second.key ?{xa_ys_zz_s}
third.key ?{xa_k}
$
$

This can probably be simplified; however, obvious simplifications did not seem to work. Smilie It's trickier than it looks.
Code:
sed -e :a -e's/\([^{]\+{[^.]\+\)\./\1_/;ta' < data

This simplification worked for me.... interesting, I did not know about the "t" operator.
# 5  
Old 10-01-2008
Quote:
Originally Posted by gnsxhj
if u don't mind, i can try this in awk instead of sed
Code:
awk -v FS='[}{]' '{gsub(/\./,"_",$2); print $1"{"$2"}"}' /path/of/file

Sweet thinking!
# 6  
Old 10-01-2008
Thanks Perderabo and gnsxhj... I'm still, however, interested in a pure (or purer?) regex solution.
# 7  
Old 10-02-2008
Code:
$ cat file
first.key ?{x.y.z}
second.key ?{xa.ys.zz.s}
third.key ?{xa.k}
$ perl -pe's/([^.]+)\.(?!\w+\s)/$1_/g' file
first.key ?{x_y_z}
second.key ?{xa_ys_zz_s}
third.key ?{xa_k}

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