Problem matching parenthesis in awk regex

Question

I have this expression

if lbVar and ldcVar < 0.00

And i need to match the right part of "and" that may contain parenthesis.

The expression to match without the parenthesis is already done:

 if(match(linha, /(\t| )*(and)(\t| )+(\<ldc\w*)[ \t]*(<)[ \t]*(ldc\w*|[0-9]|[0-9]+(\.[0-9]*))/) > 0){ 
        print "match: "substr($0, RSTART, RLENGTH);
    }

The problem is the expression may appear as:

if lbVar and ( ldcVar < 0.00 )

How can i correct my regex so that match both situation, that is, with or without parenthesis?

Thanks

Please do mention sample of input and expected output in your post and let us know then. — RavinderSingh13, Jan 21 '20 at 14:52
Does this answer your question? [RegEx to match stuff between parentheses](https://stackoverflow.com/questions/6208367/regex-to-match-stuff-between-parentheses) — Benoît Zu, Jan 21 '20 at 15:00
You have asked a few questions about regex matching. Perhaps you want to build a parser for this language instead. — glenn jackman, Jan 21 '20 at 16:14

score 0 · Answer 1 · answered Jan 21 '20 at 17:47

0

There are few typos in the sequence. Trying using the modified RE below

if(match(line, /(\t| )*(and)(\t| )(\(+)(\t| )*(\<ldc\w*)[ \t]*(<)[ \t]*(ldc\w*|[0-9]+|[0-9]+(\.[0-9]*))[ \t]*(\))/) ) {
    print "SUB: ="substr($0, RSTART, RLENGTH) "=" 
}

Also, consider changing the (\t| )* to [\t ]* (for efficiency/simplification).

answered Jan 21 '20 at 17:47

dash-o

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I made the test but unfortunately didn´t match – user2753544 Jan 21 '20 at 19:33
1

You should mention that requires GNU awk for `\<`. – Ed Morton Jan 21 '20 at 20:03
1

@EdMorton Thanks for highlighting this. Side note: I believe that the `\<` is not needed at all in the pattern, as the pattern require tab/space/'<' before the 'ldc' token. – dash-o Jan 22 '20 at 07:41
Could be. Right now in a non-gawk that `\<` means your regexp requires a literal `<` before the `ldc`. – Ed Morton Jan 22 '20 at 14:36
I just noticed you have `\w` in the regexp - that's non-POSIX (gawk-only?) too. – Ed Morton Jan 23 '20 at 15:35

score 0 · Answer 2 · answered Jan 21 '20 at 18:12

0

If this isn't all you need:

awk 'match($0,/.*[[:space:]]+and[[:space:]]+/){print substr($0,RLENGTH+1)}' file
( ldcVar < 0.00 )

then update your question to clarify your requirements and provide a more representative sample input/output that we can test a potential solution against for a simple pass/fail result.

answered Jan 21 '20 at 18:12

Ed Morton

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This isn't what i need. The regex must match the right part of the and , and match if the right part is between parenthesis, like the example: if lbVar and ( ldcVar < 0.00 ) – user2753544 Jan 21 '20 at 19:46
then update your question to better describe your requirements and provide a better example – Ed Morton Jan 22 '20 at 14:34
OK, there still isn't a good enough description or enough matching and non-matching in-context use cases present in your question for me personally to be able to help you more (1 sunny-day input example doesn't tell us much and I still don't know if the parentheses are required or not) but hopefully someone else will be able to. Good luck! – Ed Morton Jan 23 '20 at 15:29

Problem matching parenthesis in awk regex

2 Answers2