Regexp: rubular VS match. Why is the result different?

ruby-talk
1

I have to capture by means of regexp the content between '<' and '>'

as instance:

str = 'anystring<hour>anystring<min>anystring<sec>anystring'
I need the array['hour','min,'sec']

I have written the regexp: /(<([^<>]+)>)+/
and I have tested it in rubular.com site (It work !)

I have run it in irb:

/(<([^<>]+)>)+/.match('anystring<hour>anystring<min>anystring<sec>anystring')

=> #<MatchData "<hour>" 1:"<hour>" 2:"hour">

As you can see match method return just the first match in MatchData obj

Do you know why ?

thank you,
Alessandro

···

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Posted via http://www.ruby-forum.com/\.

2

I have to capture by means of regexp the content between '<' and '>'

as instance:

str = 'anystring<hour>anystring<min>anystring<sec>anystring'
I need the array['hour','min,'sec']

I have written the regexp: /(<([^<>]+)>)+/
and I have tested it in rubular.com site (It work !)

The "+" at the end is superfluous because this would match multiple
concatenated sequences like <xx><yyy> which you want as separate
items.

I have run it in irb:

/(<([^<>]+)>)+/.match('anystring<hour>anystring<min>anystring<sec>anystring')

=> #<MatchData "<hour>" 1:"<hour>" 2:"hour">

As you can see match method return just the first match in MatchData obj

Do you know why ?

That's the difference between #match and #scan. You want scan in your code.

irb(main):001:0> str = 'anystring<hour>anystring<min>anystring<sec>anystring'
=> "anystring<hour>anystring<min>anystring<sec>anystring"
irb(main):002:0> str.scan /<([^>]+)>/
=> [["hour"], ["min"], ["sec"]]
irb(main):003:0> str.scan /<([^>]+)>/ do |m| p m end
["hour"]
["min"]
["sec"]
=> "anystring<hour>anystring<min>anystring<sec>anystring"
irb(main):004:0> str.scan /<([^>]+)>/ do |m,| p m end
"hour"
"min"
"sec"
=> "anystring<hour>anystring<min>anystring<sec>anystring"

Kind regards

robert

···

2009/10/28 Ale Ds <alexdesi@gmail.com>:

--
remember.guy do |as, often| as.you_can - without end
http://blog.rubybestpractices.com/

3

Alessandro,

You'll want the String#scan method (RDoc Documentation
classes/String.html#M000812).

  015:0> regexp = /<([^<>]+)>/
  => /<([^<>]+)>/
  016:0> str = 'anystring<hour>anystring<min>anystring<sec>anystring'
  => "anystring<hour>anystring<min>anystring<sec>anystring"
  017:0> str.scan(regexp)
  => [["hour"], ["min"], ["sec"]]

HTH,
Chris

···

On Oct 28, 10:12 am, Ale Ds <alexd...@gmail.com> wrote:

I have to capture by means of regexp the content between '<' and '>'

as instance:

str = 'anystring<hour>anystring<min>anystring<sec>anystring'
I need the array['hour','min,'sec']

I have written the regexp: /(<([^<>]+)>)+/
and I have tested it in rubular.com site (It work !)

I have run it in irb:>> /(<([^<>]+)>)+/.match('anystring<hour>anystring<min>anystring<sec>anystring')

=> #<MatchData "<hour>" 1:"<hour>" 2:"hour">

As you can see match method return just the first match in MatchData obj

Do you know why ?

thank you,
Alessandro
--
Posted viahttp://www.ruby-forum.com/.

4

The "+" at the end is superfluous because this would match multiple
concatenated sequences like <xx><yyy> which you want as separate
items.

...
I agree with you

I have run it in irb:

/(<([^<>]+)>)+/.match('anystring<hour>anystring<min>anystring<sec>anystring')

=> #<MatchData "<hour>" 1:"<hour>" 2:"hour">

As you can see match method return just the first match in MatchData obj

Do you know why ?

That's the difference between #match and #scan. You want scan in your
code.

...

yes, scan works !
thanks a lot,
Alessandro

···

--
Posted via http://www.ruby-forum.com/\.

5

You'll want the String#scan method (RDoc Documentation
classes/String.html#M000812).

Yes, at first time I didn't find scan method because I searched it in
Match obj (instead of String obj)

thank you
Alessandro

···

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Posted via http://www.ruby-forum.com/\.