fix Morpheme.from_segments

Author: arubehn

src/linse/typedsequence.py

@@ -151,7 +151,10 @@ def from_string(cls, s, separator=None):
 
     @classmethod
     def from_segments(cls, s, separator=None):
-        return s.split(separator) if separator else s.split()
+        if separator.strip():  # if the separator is something else than whitespaces in any form
+            separator = "\s*" + re.escape(separator) + "\s*"
+        segments = re.split(separator, s) if separator else s.split()
+        return cls(segments)
 
     def to_text(self):
         return ''.join(self)