Hi.
I'm hoping that someone can give me some pointers. I need to match the
content within the parentheses only, from the following string (this is
an example string, but the structure is consistent):
d_(1)+d_(23)
So far I have matched something else using \b to match a closing tic
(`), but that doesn't seem to work here:
\_\((.+)\b[^)]
Best regards
// Emil
--
Posted via http://www.ruby-forum.com/.
I think /\(([^)]+)\)/ should work.
For your example string:
"d_(1)+d_(23)".scan(/\(([^)]+)\)/)
#=> [["1"],["23"]]
--
gunther
2011/3/24 Emil Kampp <ekampp@gmail.com>
Hi.
I'm hoping that someone can give me some pointers. I need to match the
content within the parentheses only, from the following string (this is
an example string, but the structure is consistent):d_(1)+d_(23)
So far I have matched something else using \b to match a closing tic
(`), but that doesn't seem to work here:\_\((.+)\b[^)]
Best regards
// Emil--
Posted via http://www.ruby-forum.com/\.
Thank you, that pointed me in the right direction. But now I'm facing
another problem (still kinda the same). I have this string:
f_(a)(x)=x^(2)+(5x//f'(x))
Where i need to capture everything within the parentheses surrounding
the double-slashes (//), like so:
(5x//f'(x))
My problem is that I can't seem to get past the last parentheses around
the f'(x). This is what I've gotten so far:
(([^(]*)\/\/[^\)]*)
And that will match `5x//f'(x`, so I need to get past that last closing
parentheses around the x.
I hope that someone (Gunther, if you'r still up for it?) can help me.
Best regards
// Emil
--
Posted via http://www.ruby-forum.com/.
Regexes are "greedy" by default. Don't look for [^)] characters,
instead look for a closing parentheses:
str = "aaa( abc(def)ghi (jkl)(mno) )"
if (str =~ /[(] .* [)]/xms )
puts Regexp.last_match[0]
end
--output:--
( abc(def)ghi (jkl)(mno) )
How you will know when to use non-greedy patterns, like [^)] or .*?,
versus the natural greediness of a regex is not clear to me.
--
Posted via http://www.ruby-forum.com/.
I have upgraded the regular expression somewhat, to enclose other
similar situations, but I still have the problem of not getting the last
parenthesis (the one completely ending the statement) included in the
expression (while not grabbing anything beyond the parentheses).
This is the upgraded expression:
((\()([^(]*)\/\/([^)]*)(\)))
// Emil
--
Posted via http://www.ruby-forum.com/.
perl's regexes have a recursive feature, which can solve your problem.
Want to call an external script?
--
Posted via http://www.ruby-forum.com/.
Thank you people. I will try and work with this stuff. It has given an
entry point into where to start, so that's fantastic.
// Emil
--
Posted via http://www.ruby-forum.com/.
Not necessary: Ruby has it, too.
irb(main):001:0> s="x(a(b)()c)y"
=> "x(a(b)()c)y"
irb(main):002:0> %r{(?<ne> \( (?:\g<ne>|[^()]+)* \) )}x.match s
=> #<MatchData "(a(b)()c)" ne:"(a(b)()c)">
irb(main):003:0> s = "f_(a)(x)=x^(2)+(5x//f'(x))"
=> "f_(a)(x)=x^(2)+(5x//f'(x))"
irb(main):004:0> s.scan %r{(?<ne> \( (?: \g<ne> | [^()] )* \) )}x
=> [["(a)"], ["(x)"], ["(2)"], ["(5x//f'(x))"]]
See サービス終了のお知らせ
Kind regards
robert
On Fri, Mar 25, 2011 at 2:58 AM, 7stud -- <bbxx789_05ss@yahoo.com> wrote:
perl's regexes have a recursive feature, which can solve your problem.
Want to call an external script?
--
remember.guy do |as, often| as.you_can - without end
http://blog.rubybestpractices.com/
PS: Here's a more targeted one
irb(main):054:0> %r{\( (?<ne> [^()] | \( \g<ne> \) )* // \g<ne>* \)}x.match s
=> #<MatchData "(5x//f'(x))" ne:"(x)">
Cheers
robert
On Fri, Mar 25, 2011 at 9:14 AM, Robert Klemme <shortcutter@googlemail.com> wrote:
On Fri, Mar 25, 2011 at 2:58 AM, 7stud -- <bbxx789_05ss@yahoo.com> wrote:
perl's regexes have a recursive feature, which can solve your problem.
Want to call an external script?Not necessary: Ruby has it, too.
irb(main):001:0> s="x(a(b)()c)y"
=> "x(a(b)()c)y"
irb(main):002:0> %r{(?<ne> \( (?:\g<ne>|[^()]+)* \) )}x.match s
=> #<MatchData "(a(b)()c)" ne:"(a(b)()c)">irb(main):003:0> s = "f_(a)(x)=x^(2)+(5x//f'(x))"
=> "f_(a)(x)=x^(2)+(5x//f'(x))"
irb(main):004:0> s.scan %r{(?<ne> \( (?: \g<ne> | [^()] )* \) )}x
=> [["(a)"], ["(x)"], ["(2)"], ["(5x//f'(x))"]]See サービス終了のお知らせ
--
remember.guy do |as, often| as.you_can - without end
http://blog.rubybestpractices.com/
Robert K. wrote in post #989148:
On Fri, Mar 25, 2011 at 2:58 AM, 7stud -- <bbxx789_05ss@yahoo.com> > wrote:
perl's regexes have a recursive feature, which can solve your problem.
Want to call an external script?Not necessary: Ruby has it, too.
irb(main):002:0> %r{(?<ne> \( (?:\g<ne>|[^()]+)* \) )}x
How come the perl regex uses the non-backtracking ++, and yours doesn't
appear to do the equivalent?
--
Posted via http://www.ruby-forum.com/\.
... and if you want to extract the content of the outer bracket
automatically you can do
irb(main):007:0> md = %r{\( (?<all> (?<ne> [^()] | \( \g<ne> \) )* //
\g<ne>* ) \)}x.match s
=> #<MatchData "(5x//f'(x))" all:"5x//f'(x)" ne:"(x)">
irb(main):008:0> md[:all]
=> "5x//f'(x)"
Kind regards
robert
On Fri, Mar 25, 2011 at 9:28 AM, Robert Klemme <shortcutter@googlemail.com> wrote:
On Fri, Mar 25, 2011 at 9:14 AM, Robert Klemme > <shortcutter@googlemail.com> wrote:
On Fri, Mar 25, 2011 at 2:58 AM, 7stud -- <bbxx789_05ss@yahoo.com> wrote:
perl's regexes have a recursive feature, which can solve your problem.
Want to call an external script?Not necessary: Ruby has it, too.
irb(main):001:0> s="x(a(b)()c)y"
=> "x(a(b)()c)y"
irb(main):002:0> %r{(?<ne> \( (?:\g<ne>|[^()]+)* \) )}x.match s
=> #<MatchData "(a(b)()c)" ne:"(a(b)()c)">irb(main):003:0> s = "f_(a)(x)=x^(2)+(5x//f'(x))"
=> "f_(a)(x)=x^(2)+(5x//f'(x))"
irb(main):004:0> s.scan %r{(?<ne> \( (?: \g<ne> | [^()] )* \) )}x
=> [["(a)"], ["(x)"], ["(2)"], ["(5x//f'(x))"]]See サービス終了のお知らせ
PS: Here's a more targeted one
irb(main):054:0> %r{\( (?<ne> [^()] | \( \g<ne> \) )* // \g<ne>* \)}x.match s
=> #<MatchData "(5x//f'(x))" ne:"(x)">
--
remember.guy do |as, often| as.you_can - without end
http://blog.rubybestpractices.com/
"_the_ perl regexp"? What do you mean exactly?
Kind regards
robert
On 26.03.2011 04:08, 7stud -- wrote:
Robert K. wrote in post #989148:
On Fri, Mar 25, 2011 at 2:58 AM, 7stud --<bbxx789_05ss@yahoo.com> >> wrote:
perl's regexes have a recursive feature, which can solve your problem.
Want to call an external script?Not necessary: Ruby has it, too.
irb(main):002:0> %r{(?<ne> \( (?:\g<ne>|[^()]+)* \) )}x
How come the perl regex uses the non-backtracking ++, and yours doesn't
appear to do the equivalent?
--
remember.guy do |as, often| as.you_can - without end
http://blog.rubybestpractices.com/