Loading ...
Sorry, an error occurred while loading the content.
 

Re: [NTS] Re: regular expression to find anything up to two spaces in a row ...

Expand Messages
  • Don
    I am actually exporting this one to another purpose, but testing in both notetab and regex buddy.
    Message 1 of 13 , Jun 20, 2011
      I am actually exporting this one to another purpose, but testing in both
      notetab and regex buddy.

      On 6/20/2011 2:33 PM, Axel Berger wrote:
      > Eb wrote:
      >> Move the quatifier outside of the class, Inside the class you're
      >> just adding the "{2}" characters to the class.
      >> ([^ ]{2})
      >
      > Nope. What you suggest equals "two instances of 'not space'". What Don
      > wants is "anything but two spaces in row". Quite different.
      >
      > All your finds will have a length of exactly two and they can't include
      > even a single space.
      >
      > There really is no single-step solution for this, but then, as long as
      > clips is doing all the work and I don't have to, I really don't mind how
      > many steps it takes.
      >
      > Axel
    • Eb
      Right you are. I started out commenting on the placement of quatifiers. Then I was on a roll, but forgot about the _not_ two spaces. ... Actually, I would
      Message 2 of 13 , Jun 21, 2011
        Right you are.

        I started out commenting on the placement of quatifiers.

        Then I was on a roll, but forgot about the _not_ two spaces.

        --- In ntb-scripts@yahoogroups.com, Axel Berger <Axel-Berger@...> wrote:
        > Nope. What you suggest equals "two instances of 'not space'". What Don
        > wants is "anything but two spaces in row". Quite different.
        >
        > All your finds will have a length of exactly two and they can't include
        > even a single space.
        >
        > There really is no single-step solution for this, but then, as long


        Actually, I would expect the assertion:

        (?= )

        to find a string ending in 2 spaces, without including the two spaces in the match.

        Eb
      • Axel Berger
        ... Yes, you re right and that s probably better than my ^!Find (?s)(.+?)( {2,}) RSTI1 but it has the same problem. Don specified ... which I took to mean
        Message 3 of 13 , Jun 21, 2011
          Eb wrote:
          > Actually, I would expect the assertion:
          > (?= )
          > to find a string ending in 2 spaces, without including the
          > two spaces in the match.

          Yes, you're right and that's probably better than my

          ^!Find "(?s)(.+?)( {2,})" RSTI1

          but it has the same problem. Don specified
          > everything and anything unless until I
          > encounter two spaces in a row ...
          which I took to mean the two spaces may or may not occur, as is usual
          when using negative classes. If they're certain to do, then things get
          much easier.

          Axel
        • Don
          Yes the two spaces are certain to occur :-) I am limited I supposed in my understanding so I didn t make the assumption you made. Now that you explain it like
          Message 4 of 13 , Jun 21, 2011
            Yes the two spaces are certain to occur :-)

            I am limited I supposed in my understanding so I didn't make the
            assumption you made. Now that you explain it like that I guess it makes
            sense. What I am trying to do is use two spaces as a delimiter in
            essence. I will actually be discarding the spaces as unnecessary in
            what I am doing.

            Off to look up (?= ) and see what it means.

            On 6/21/2011 7:54 PM, Axel Berger wrote:
            > Eb wrote:
            >> Actually, I would expect the assertion:
            >> (?= )
            >> to find a string ending in 2 spaces, without including the
            >> two spaces in the match.
            >
            > Yes, you're right and that's probably better than my
            >
            > ^!Find "(?s)(.+?)( {2,})" RSTI1
            >
            > but it has the same problem. Don specified
            >> everything and anything unless until I
            >> encounter two spaces in a row ...
            > which I took to mean the two spaces may or may not occur, as is usual
            > when using negative classes. If they're certain to do, then things get
            > much easier.
            >
            > Axel
            >
            >
            > ------------------------------------
            >
            > Fookes Software: http://www.fookes.com/
            > NoteTab website: http://www.notetab.com/
            > NoteTab Discussion Lists: http://www.notetab.com/groups.php
            >
            > ***
            > Yahoo! Groups Links
            >
            >
            >
            >
          • Don
            From Regex Buddy (my newest friend ...): Positive lookahead works just the same. q(?=u) matches a q that is followed by a u, without making the u part of the
            Message 5 of 13 , Jun 21, 2011
              From Regex Buddy (my newest friend ...):

              "Positive lookahead works just the same. q(?=u) matches a q that is
              followed by a u, without making the u part of the match. The positive
              lookahead construct is a pair of round brackets, with the opening
              bracket followed by a question mark and an equals sign. You can use any
              regular expression inside the lookahead. Any valid regular expression
              can be used inside the lookahead."

              If I understand correctly, I can then actually do this:
              (?=( ))
              and create a back-reference if I wish?

              Learning as I go here :-) and it's fun. Thanks Axel and Eb!


              On 6/21/2011 7:54 PM, Axel Berger wrote:
              > Eb wrote:
              >> Actually, I would expect the assertion:
              >> (?= )
              >> to find a string ending in 2 spaces, without including the
              >> two spaces in the match.
              >
              > Yes, you're right and that's probably better than my
              >
              > ^!Find "(?s)(.+?)( {2,})" RSTI1
              >
              > but it has the same problem. Don specified
              >> everything and anything unless until I
              >> encounter two spaces in a row ...
              > which I took to mean the two spaces may or may not occur, as is usual
              > when using negative classes. If they're certain to do, then things get
              > much easier.
              >
              > Axel
              >
              >
              > ------------------------------------
              >
              > Fookes Software: http://www.fookes.com/
              > NoteTab website: http://www.notetab.com/
              > NoteTab Discussion Lists: http://www.notetab.com/groups.php
              >
              > ***
              > Yahoo! Groups Links
              >
              >
              >
              >
            • John Shotsky
              [Off to look up (?= ) and see what it means.] I use it often. It is the inverse of K - which doesn t capture anything before, but it evaluates it. (?=), when
              Message 6 of 13 , Jun 21, 2011
                [Off to look up (?= ) and see what it means.]

                I use it often. It is the inverse of \K - which doesn't capture anything before, but it evaluates it. (?=), when used in
                a regex, is exactly the same, meaning anything that follows is not captured, but is evaluated.



                So, this:

                "this that"

                Run on:

                ^!Replace "this\x20\K(?=that)" >> "with\x20" ARSW

                Produces "this with that"

                Pretty handy for inserting something without any capturing.

                Regards,

                John



                From: ntb-scripts@yahoogroups.com [mailto:ntb-scripts@yahoogroups.com] On Behalf Of Don
                Sent: Tuesday, June 21, 2011 18:23
                To: ntb-scripts@yahoogroups.com
                Subject: Re: [NTS] Re: regular expression to find anything up to two spaces in a row ...





                Yes the two spaces are certain to occur :-)

                I am limited I supposed in my understanding so I didn't make the
                assumption you made. Now that you explain it like that I guess it makes
                sense. What I am trying to do is use two spaces as a delimiter in
                essence. I will actually be discarding the spaces as unnecessary in
                what I am doing.

                Off to look up (?= ) and see what it means.

                On 6/21/2011 7:54 PM, Axel Berger wrote:
                > Eb wrote:
                >> Actually, I would expect the assertion:
                >> (?= )
                >> to find a string ending in 2 spaces, without including the
                >> two spaces in the match.
                >
                > Yes, you're right and that's probably better than my
                >
                > ^!Find "(?s)(.+?)( {2,})" RSTI1
                >
                > but it has the same problem. Don specified
                >> everything and anything unless until I
                >> encounter two spaces in a row ...
                > which I took to mean the two spaces may or may not occur, as is usual
                > when using negative classes. If they're certain to do, then things get
                > much easier.
                >
                > Axel
                >
                >
                > ------------------------------------
                >
                > Fookes Software: http://www.fookes.com/
                > NoteTab website: http://www.notetab.com/
                > NoteTab Discussion Lists: http://www.notetab.com/groups.php
                >
                > ***
                > Yahoo! Groups Links
                >
                >
                >
                >





                [Non-text portions of this message have been removed]
              • Art Kocsis
                John, Not quite. Look ahead and look behind assertions are very useful, I agree but K and (?
                Message 7 of 13 , Jun 22, 2011
                  John,

                  Not quite. Look ahead and look behind assertions are very useful, I agree but
                  \K and (?<=...) [the positive look behind assertion] are NOT EXACTLY the
                  same. The big difference (and what makes \K so much better), is that the
                  escape sequence \K allows variable length sub patterns whereas the positive/
                  negative look ahead/look behind assertions all require fixed length sub
                  patterns.

                  Namaste', Art

                  At 06/21/2011 19:12, John wrote:
                  >[Off to look up (?= ) and see what it means.]
                  >
                  >I use it often. It is the inverse of \K - which doesn't capture anything
                  >before, but it evaluates it.
                  >(?=), when used in a regex, is exactly the same, meaning anything that
                  >follows is not captured,
                  > but is evaluated.
                Your message has been successfully submitted and would be delivered to recipients shortly.