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No Recursive instr?!!past of my lisp programming days. There must be a function to find the nth occurrence of a string within another. instr only gives you the first one. Of course I can write a function that recurses n times to get the nth occurrence, but there must be a native version, right? To clarify, lets say I want the 3rd x in this string: strMine="xxoooxoxoxo" instrNth=(strMine, "x", 3) returning 6 Any ideas? Depending on your case, I guess you can profit from regex? e.g.:
dim re as regex = new regex(pattern, regexoptions.multiline) ' e.g. pattern = "x" dim myMatches as matchcollection = re.matches(source-string) 'e.g. source-string = "xxooxoxoxo" myMatches(n) = n'th occurrence of some match 'e.g. myMatches(2) = x myMatches(n).index = the index of the n'th occ. 'e.g. myMatches(2).index = 4 anyway - it's more pretty than writing a recursive instr function, I guess... Anil Gupte skrev: Show quoteHide quote > I must have missed it. It cannot be possible. Or may be I am living in the > past of my lisp programming days. > > There must be a function to find the nth occurrence of a string within > another. instr only gives you the first one. Of course I can write a > function that recurses n times to get the nth occurrence, but there must be > a native version, right? To clarify, lets say I want the 3rd x in this > string: > > strMine="xxoooxoxoxo" > > instrNth=(strMine, "x", 3) > returning 6 > > Any ideas? > -- > Anil Gupte > www.keeninc.net > www.icinema.com Wow! Regex is quite comprehensive - I will have to sit down and study it
for a while, before I can use it. Thanx! Show quoteHide quote "Maate" <mor***@m8solutions.dk> wrote in message news:1159279826.720431.178200@m73g2000cwd.googlegroups.com... > > Depending on your case, I guess you can profit from regex? e.g.: > > dim re as regex = new regex(pattern, regexoptions.multiline) ' e.g. > pattern = "x" > dim myMatches as matchcollection = re.matches(source-string) 'e.g. > source-string = "xxooxoxoxo" > > myMatches(n) = n'th occurrence of some match 'e.g. myMatches(2) = x > myMatches(n).index = the index of the n'th occ. 'e.g. > myMatches(2).index = 4 > > anyway - it's more pretty than writing a recursive instr function, I > guess... > > > > Anil Gupte skrev: > >> I must have missed it. It cannot be possible. Or may be I am living in >> the >> past of my lisp programming days. >> >> There must be a function to find the nth occurrence of a string within >> another. instr only gives you the first one. Of course I can write a >> function that recurses n times to get the nth occurrence, but there must >> be >> a native version, right? To clarify, lets say I want the 3rd x in this >> string: >> >> strMine="xxoooxoxoxo" >> >> instrNth=(strMine, "x", 3) >> returning 6 >> >> Any ideas? >> -- >> Anil Gupte >> www.keeninc.net >> www.icinema.com > "Anil Gupte" <anil-l***@icinema.com> schrieb: I'd use the iterative approach: Call 'InStr' until either the end of the >I must have missed it. It cannot be possible. Or may be I am living in >the past of my lisp programming days. > > There must be a function to find the nth occurrence of a string within > another. instr only gives you the first one. Of course I can write a > function that recurses n times to get the nth occurrence, but there must > be a native version, right? To clarify, lets say I want the 3rd x in this > string: string is reached or the n-th occurance has been found. -- M S Herfried K. Wagner M V P <URL:http://dotnet.mvps.org/> V B <URL:http://dotnet.mvps.org/dotnet/faqs/> 
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