Allow calling join() with strs

typon/trans/transpiler/phases/emit_cpp/__init__.py

@@ -17,7 +17,7 @@ class UniversalVisitor:
     def visit(self, node):
         """Visit a node."""
         TB = f"emitting C++ code for {highlight(node)}"
-        #TB_SKIP = True
+        # TB_SKIP = True
 
         if type(node) == list:
             for n in node:
@@ -113,6 +113,7 @@ class NodeVisitor(UniversalVisitor):
         else:
             raise NotImplementedError(node)
 
+
 class CoroutineMode(Flag):
     SYNC = 1
     FAKE = 2 | SYNC
@@ -121,21 +122,32 @@ class CoroutineMode(Flag):
     TASK = 16 | ASYNC
     JOIN = 32 | ASYNC
 
+
 class FunctionEmissionKind(enum.Enum):
     DECLARATION = enum.auto()
     DEFINITION = enum.auto()
     METHOD = enum.auto()
     LAMBDA = enum.auto()
 
+
 def join(sep: str, items: Iterable[Iterable[str]]) -> Iterable[str]:
     items = iter(items)
     try:
-        yield from next(items)
+        it = next(items)
+        if type(it) is str:
+            yield it
+        else:
+            yield from it
         for item in items:
             yield sep
-            yield from item
+            it = item
+            if type(it) is str:
+                yield it
+            else:
+                yield from it
     except StopIteration:
         return
 
+
 def flatmap(f, items):
     return chain.from_iterable(map(f, items))