Refactor tokenizer

smnp/error/syntax.py

@@ -0,0 +1,4 @@
+class SyntaxException(Exception):
+    def __init__(self, pos, msg):        
+        posStr = "" if pos is None else f"[line {pos[0]+1}, col {pos[1]+1}]"        
+        self.msg = f"Syntax error {posStr}:\n{msg}"