1 files changed, 35 insertions, 9 deletions
diff --git a/html_render.py b/html_render.py
index 533ae7c..99140ad 100644
--- a/html_render.py
+++ b/html_render.py
@@ -1,23 +1,24 @@
 import html
 from typing import (
+    Callable,
     TypeAlias,
     Union,
-    Callable,
-    Optional,
-    cast,
 )
 
-HTML: TypeAlias = Union[tuple, list, Callable[[], str], None,
-                        str, int, float]
+HTML: TypeAlias = Union[tuple,
+                        list['HTML'],
+                        Callable[[], str],
+                        None, str, int, float]
 
 
 standalones = ['hr', 'br', 'meta']
+"""Tags which can't have a closing tag."""
 
 
 def _render_document(document: HTML) -> str:
-    if type(document) == tuple:
+    if isinstance(document, tuple):
         tag, *body = document
-        if body and type(body[0]) == dict:
+        if body and isinstance(body[0], dict):
             print(body[0])
             attributes = ' '.join(f'{a}="{html.escape(b)}"'
                                   for a, b in body[0].items())
@@ -25,14 +26,18 @@ def _render_document(document: HTML) -> str:
             start = f'<{tag} {attributes}>'
         else:
             start = f'<{tag}>'
+
         if tag in standalones:
             return start
         else:
-            items = ''.join(_render_document(b) for b in body)
+            if body:
+                items = ''.join(_render_document(b) for b in body)
+            else:
+                items = ''
             return start + f'{items}</{tag}>'
     elif callable(document):
         return str(document())
-    elif type(document) == list:
+    elif isinstance(document, list):
         return ''.join(_render_document(e) for e in document)
     elif document is None:
         return ''
@@ -42,4 +47,25 @@ def _render_document(document: HTML) -> str:
 
 
 def render_document(document: HTML) -> str:
+    """
+    Render an HTML structure to an Html string.
+
+    The following Python types are converted as follows:
+    - Tuples
+      - The first value becomes the tags name
+      - The second value, if a dictionary, becomes the tags attributes
+      - All following values (including the second if not a dictionary)
+        gets individually passed to render_document.
+    - Lists
+      Each element gets passed to render_document
+    - Callable[[], str]
+      Gets called, and its output is included verbatim. Useful for
+      including strings which shouldn't be escaped.
+    - str
+      Gets escaped, and included
+    - int, float
+      Gets included as their default string representation.
+    - None
+      Becomes an empty string
+    """
     return '<!doctype html>\n' + _render_document(document)