iterator split*(s: string, sep: char): var string =
  var last = 0
  var res = newstring(256)
  assert('\0' != sep)
  if len(s) > 0:
    while last <= len(s):
      var first = last
      while last < len(s) and s[last] != sep: 
        inc(last)
 
      let len = last-first
      if len < 1:
        res.setLen 0
      else:
        res.setLen len
        copymem res[0], s[first].addr, L
      yield res ##yield substr(s, first, last-1)
      inc(last)
 
const str = """
Hello
 
 
hello
hello
 
"""
 
for x in str.split('\L'):
  echo x.len, " \"", x, '"'
 
 

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