diff options
Diffstat (limited to 'lib/impure/re.nim')
| -rw-r--r-- | lib/impure/re.nim | 64 |
1 files changed, 36 insertions, 28 deletions
diff --git a/lib/impure/re.nim b/lib/impure/re.nim index c7f8f336b..a60f70828 100644 --- a/lib/impure/re.nim +++ b/lib/impure/re.nim @@ -7,18 +7,14 @@ # distribution, for details about the copyright. # -## Regular expression support for Nim. This module still has some -## obscure bugs and limitations, -## consider using the ``nre`` or ``pegs`` modules instead. -## We had to de-deprecate this module since too much code relies on it -## and many people prefer its API over ``nre``'s. +## Regular expression support for Nim. ## ## This module is implemented by providing a wrapper around the -## `PRCE (Perl-Compatible Regular Expressions) <http://www.pcre.org>`_ -## C library. This means that your application will depend on the PRCE +## `PCRE (Perl-Compatible Regular Expressions) <http://www.pcre.org>`_ +## C library. This means that your application will depend on the PCRE ## library's licence when using this module, which should not be a problem ## though. -## PRCE's licence follows: +## PCRE's licence follows: ## ## .. include:: ../../doc/regexprs.txt ## @@ -117,7 +113,7 @@ proc matchOrFind(buf: cstring, pattern: Regex, matches: var openArray[string], var b = rawMatches[i * 2 + 1] if a >= 0'i32: matches[i-1] = bufSubstr(buf, int(a), int(b)) - else: matches[i-1] = nil + else: matches[i-1] = "" return rawMatches[1] - rawMatches[0] proc findBounds*(buf: cstring, pattern: Regex, matches: var openArray[string], @@ -137,7 +133,7 @@ proc findBounds*(buf: cstring, pattern: Regex, matches: var openArray[string], var a = rawMatches[i * 2] var b = rawMatches[i * 2 + 1] if a >= 0'i32: matches[i-1] = bufSubstr(buf, int(a), int(b)) - else: matches[i-1] = nil + else: matches[i-1] = "" return (rawMatches[0].int, rawMatches[1].int - 1) proc findBounds*(s: string, pattern: Regex, matches: var openArray[string], @@ -291,7 +287,7 @@ proc find*(buf: cstring, pattern: Regex, matches: var openArray[string], var a = rawMatches[i * 2] var b = rawMatches[i * 2 + 1] if a >= 0'i32: matches[i-1] = bufSubstr(buf, int(a), int(b)) - else: matches[i-1] = nil + else: matches[i-1] = "" return rawMatches[0] proc find*(s: string, pattern: Regex, matches: var openArray[string], @@ -460,8 +456,6 @@ proc replacef*(s: string, sub: Regex, by: string): string = while true: var match = findBounds(s, sub, caps, prev) if match.first < 0: break - assert result != nil - assert s != nil add(result, substr(s, prev, match.first-1)) addf(result, by, caps) prev = match.last + 1 @@ -502,7 +496,7 @@ proc transformFile*(infile, outfile: string, var x = readFile(infile).string writeFile(outfile, x.multiReplace(subs)) -iterator split*(s: string, sep: Regex): string = +iterator split*(s: string, sep: Regex; maxsplit = -1): string = ## Splits the string ``s`` into substrings. ## ## Substrings are separated by the regular expression ``sep`` @@ -524,22 +518,28 @@ iterator split*(s: string, sep: Regex): string = ## "example" ## "" ## - var - first = -1 - last = -1 - while last < len(s): - var x = matchLen(s, sep, last) - if x > 0: inc(last, x) - first = last - if x == 0: inc(last) + var last = 0 + var splits = maxsplit + var x: int + while last <= len(s): + var first = last + var sepLen = 1 while last < len(s): x = matchLen(s, sep, last) - if x >= 0: break + if x >= 0: + sepLen = x + break inc(last) - if first <= last: - yield substr(s, first, last-1) - -proc split*(s: string, sep: Regex): seq[string] {.inline.} = + if x == 0: + if last >= len(s): break + inc last + if splits == 0: last = len(s) + yield substr(s, first, last-1) + if splits == 0: break + dec(splits) + inc(last, sepLen) + +proc split*(s: string, sep: Regex, maxsplit = -1): seq[string] {.inline.} = ## Splits the string ``s`` into a seq of substrings. ## ## The portion matched by ``sep`` is not returned. @@ -613,7 +613,7 @@ when isMainModule: doAssert false if "abc" =~ re"(cba)?.*": - doAssert matches[0] == nil + doAssert matches[0] == "" else: doAssert false if "abc" =~ re"().*": @@ -636,6 +636,14 @@ when isMainModule: accum.add(word) doAssert(accum == @["AAA", "", "BBB"]) + doAssert(split("abc", re"") == @["a", "b", "c"]) + doAssert(split("", re"") == @[]) + + doAssert(split("a;b;c", re";") == @["a", "b", "c"]) + doAssert(split(";a;b;c", re";") == @["", "a", "b", "c"]) + doAssert(split(";a;b;c;", re";") == @["", "a", "b", "c", ""]) + doAssert(split("a;b;c;", re";") == @["a", "b", "c", ""]) + for x in findAll("abcdef", re"^{.}", 3): doAssert x == "d" accum = @[] |