Remove fix for previously buggy array slice

Author: oprypin

src/docopt.nim

@@ -192,7 +192,7 @@ method match(self: ChildPattern, left: seq[Pattern],
     except ValueError:
         return (false, left, collected)
     var (pos, match) = m
-    let left2 = left.sub(0, pos) & left.sub(pos+1, left.len)
+    let left2 = left[0..<pos] & left[pos+1..^1]
     var same_name: seq[Pattern] = @[]
     for a in collected:
         if a.name == self.name:

src/private/util.nim

@@ -40,12 +40,6 @@ proc is_upper*(s: string): bool =
     s == upper and upper != s.to_lower()
 
 
-proc sub*[T](s: seq[T], a, b: int): seq[T] =
-    ## Items from `a` to `b` non-inclusive
-    if a < b: s[a .. <b]
-    else: @[]
-
-
 macro gen_class*(body: stmt): stmt {.immediate.} =
     ## When applied to a type block, this will generate methods
     ## that return each type's name as a string.