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Query Regarding Regular Expression

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# 1  
Old 03-24-2009
Query Regarding Regular Expression
Can you please tell me the meaning of .*

For eg. i have a text as "Scrapple the apple"

Now here, what does a.*e will match?
# 2  
Old 03-24-2009
It means "match any character, zero or more times, and be greedy about it". And for your text it will match "apple the apple"
# 3  
Old 03-24-2009
But it is not working in my case Smilie

dsing1@[/export/home/dsing1] $ --> more exp
scrapple the apple
dsing1@[/export/home/dsing1] $ --> grep a.*e exp
scrapple the apple
# 4  
Old 03-24-2009
Yes it is. grep returns the whole line if the regex is matching, not just the match.
# 5  
Old 03-24-2009
so when i do a.*e then how will i get "apple the apple" from "scrapple the apple"
# 6  
Old 03-24-2009
Code:
$ echo "scrapple the apple"|sed 's/s.*r//1'
apple the apple

Thanks
Sha
# 7  
Old 03-24-2009
Just as a hint, for source, listings, command line examples, ... please use the [code ][/code] tags (or the '#' symbol in the advanced editor), it's easier to read.
Code:
$ perl -pe 's/.*?(a.*e).*/$1/' exp

Other people can probably add more examples (awk anyone?)
Last edited by pludi; 03-24-2009 at 10:31 AM.. Reason: sed example already there
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