Perl: Search for string on line then search and replace text

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# 1  
Old 01-03-2008
Perl: Search for string on line then search and replace text

Hi All,

I have a file that I need to be able to find a pattern match on a line, search that line for a text pattern, and replace that text.

An example of 4 lines in my file is:

1. MatchText_randomNumberOfText moreData ReplaceMe moreData
2. MatchText_randomNumberOfText moreData moreData ReplaceMe moreData moreData
3. MatchText_randomNumberOfText moreData ReplaceMe moreData moreData
4. TextTextText_randomNumberOfText moreData ReplaceMe moreData moreData

The above is an example of four lines. I want to find all the lines containing "MatchText" (lines 1,2 and 3) and replace the "ReplaceMe" in that line with "REPLACED".

"ReplaceMe" occurs multiple times in lines I do not want to replace it in (as in line 4 above)

Hope that makes sense!!
Many thanks
# 2  
Old 01-03-2008
loop through each line.

if($line =~ /MatchText/){
    $line =~ s/ReplaceMe/REPLACED/gi;

# 3  
Old 01-04-2008
perl -pi -e 's/ReplaceMe/REPLACED/ if /MatchText/' filename

# 4  
Old 01-04-2008
using sed:
sed -i '/MatchText/ s/ReplaceMe/REPLACED/' filename

# 5  
Old 01-04-2008
Thanks a million, great stuff Smilie
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