Allow semicolon at end of line

Resolves   #859.

DOCS.md

@@ -341,7 +341,6 @@ The style issues which will cause `--strict` to throw an error are:
 - use of `"hello" "world"` implicit string concatenation (use explicit `+` instead)
 - use of `from __future__` imports (Coconut does these automatically)
 - inheriting from `object` in classes (Coconut does this automatically)
-- semicolons at end of lines
 - use of `u` to denote Unicode strings (all Coconut strings are Unicode strings)
 - `f`-strings with no format expressions in them
 - commas after [statement lambdas](#statement-lambdas) (not recommended as it can be unclear whether the comma is inside or outside the lambda)

coconut/compiler/compiler.py

@@ -5399,7 +5399,8 @@ def lambdef_check(self, original, loc, tokens):
 
     def endline_semicolon_check(self, original, loc, tokens):
         """Check for semicolons at the end of lines."""
-        return self.check_strict("semicolon at end of line", original, loc, tokens, always_warn=True)
+        # only warn since this can have a real impact in jupyter notebooks (#859)
+        return self.check_strict("semicolon at end of line", original, loc, tokens, only_warn=True)
 
     def u_string_check(self, original, loc, tokens):
         """Check for Python-2-style unicode strings."""