fixes #680

Author: jph00

fastcore/_modidx.py

@@ -505,6 +505,7 @@
                               'fastcore.xml.FT.__call__': ('xml.html#ft.__call__', 'fastcore/xml.py'),
                               'fastcore.xml.FT.__getattr__': ('xml.html#ft.__getattr__', 'fastcore/xml.py'),
                               'fastcore.xml.FT.__getitem__': ('xml.html#ft.__getitem__', 'fastcore/xml.py'),
+                              'fastcore.xml.FT.__html__': ('xml.html#ft.__html__', 'fastcore/xml.py'),
                               'fastcore.xml.FT.__init__': ('xml.html#ft.__init__', 'fastcore/xml.py'),
                               'fastcore.xml.FT.__iter__': ('xml.html#ft.__iter__', 'fastcore/xml.py'),
                               'fastcore.xml.FT.__repr__': ('xml.html#ft.__repr__', 'fastcore/xml.py'),

fastcore/xml.py

@@ -146,6 +146,7 @@ def _to_attr(k,v):
         if v==False: return ''
     if isinstance(v,str): v = escape(v, quote=False)
     elif isinstance(v, Mapping): v = json.dumps(v)
+    elif hasattr(v, '__html__'): v = v.__html__()
     else: v = str(v)
     qt = '"'
     if qt in v:
@@ -209,7 +210,9 @@ def to_xml(elm, lvl=0, indent=True, do_escape=True):
     "Convert `ft` element tree into an XML string"
     return Safe(_to_xml(elm, lvl, indent, do_escape=do_escape))
 
-FT.__html__ = to_xml
+# %% ../nbs/09_xml.ipynb
+@patch
+def __html__(self:FT): return to_xml(self, indent=False)
 
 # %% ../nbs/09_xml.ipynb
 def highlight(s, lang='html'):

nbs/09_xml.ipynb

@@ -382,6 +382,7 @@
     "        if v==False: return ''\n",
     "    if isinstance(v,str): v = escape(v, quote=False)\n",
     "    elif isinstance(v, Mapping): v = json.dumps(v)\n",
+    "    elif hasattr(v, '__html__'): v = v.__html__()\n",
     "    else: v = str(v)\n",
     "    qt = '\"'\n",
     "    if qt in v:\n",
@@ -460,16 +461,26 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "dd054392",
+   "id": "7a3655e9",
    "metadata": {},
    "outputs": [],
    "source": [
     "#| export\n",
     "def to_xml(elm, lvl=0, indent=True, do_escape=True):\n",
     "    \"Convert `ft` element tree into an XML string\"\n",
-    "    return Safe(_to_xml(elm, lvl, indent, do_escape=do_escape))\n",
-    "\n",
-    "FT.__html__ = to_xml"
+    "    return Safe(_to_xml(elm, lvl, indent, do_escape=do_escape))"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "dd054392",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "#| export\n",
+    "@patch\n",
+    "def __html__(self:FT): return to_xml(self, indent=False)"
    ]
   },
   {
@@ -640,10 +651,7 @@
      "text": [
       "<div><b>Hello from Django</b></div>\n",
       "\n",
-      "<div>\n",
-      "  <p>Hello from fastcore &lt;3</p>\n",
-      "</div>\n",
-      "\n"
+      "<div><p>Hello from fastcore &lt;3</p></div>\n"
      ]
     }
    ],
@@ -655,6 +663,33 @@
     "print(_esc(Div(P('Hello from fastcore <3'))))"
    ]
   },
+  {
+   "cell_type": "markdown",
+   "id": "d7ff740e",
+   "metadata": {},
+   "source": [
+    "FT attributes are rendered with `to_xml`:"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "180074af",
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "<p value=\"<div>ho</div>\">hi</p>\n",
+      "\n"
+     ]
+    }
+   ],
+   "source": [
+    "print(to_xml(P('hi', value=Div('ho'))))"
+   ]
+  },
   {
    "cell_type": "markdown",
    "id": "5ad30d7c",