Merge pull request #94 from Salehbigdeli/master

Add Method Dispatching to class methods

Author: jph00

fastcore/dispatch.py

@@ -81,6 +81,7 @@ def __init__(self, funcs=(), bases=()):
         self.funcs,self.bases = _TypeDict(),L(bases).filter(is_not(None))
         for o in L(funcs): self.add(o)
         self.inst = None
+        self.owner = None
 
     def add(self, f):
         "Add type `t` and function `f`"
@@ -109,10 +110,12 @@ def __call__(self, *args, **kwargs):
         f = self[tuple(ts)]
         if not f: return args[0]
         if self.inst is not None: f = MethodType(f, self.inst)
+        elif self.owner is not None: f = MethodType(f, self.owner)
         return f(*args, **kwargs)
 
     def __get__(self, inst, owner):
         self.inst = inst
+        self.owner = owner
         return self
 
     def __getitem__(self, k):

nbs/03_dispatch.ipynb

@@ -378,6 +378,7 @@
     "        self.funcs,self.bases = _TypeDict(),L(bases).filter(is_not(None))\n",
     "        for o in L(funcs): self.add(o)\n",
     "        self.inst = None\n",
+    "        self.owner = None\n",
     "\n",
     "    def add(self, f):\n",
     "        \"Add type `t` and function `f`\"\n",
@@ -406,10 +407,12 @@
     "        f = self[tuple(ts)]\n",
     "        if not f: return args[0]\n",
     "        if self.inst is not None: f = MethodType(f, self.inst)\n",
+    "        elif self.owner is not None: f = MethodType(f, self.owner)\n",
     "        return f(*args, **kwargs)\n",
     "\n",
     "    def __get__(self, inst, owner):\n",
     "        self.inst = inst\n",
+    "        self.owner = owner\n",
     "        return self\n",
     "\n",
     "    def __getitem__(self, k):\n",
@@ -550,7 +553,7 @@
     {
      "data": {
       "text/markdown": [
-       "<h4 id=\"TypeDispatch.add\" class=\"doc_header\"><code>TypeDispatch.add</code><a href=\"__main__.py#L10\" class=\"source_link\" style=\"float:right\">[source]</a></h4>\n",
+       "<h4 id=\"TypeDispatch.add\" class=\"doc_header\"><code>TypeDispatch.add</code><a href=\"__main__.py#L11\" class=\"source_link\" style=\"float:right\">[source]</a></h4>\n",
        "\n",
        "> <code>TypeDispatch.add</code>(**`f`**)\n",
        "\n",
@@ -873,7 +876,7 @@
     {
      "data": {
       "text/markdown": [
-       "<h4 id=\"TypeDispatch.__call__\" class=\"doc_header\"><code>TypeDispatch.__call__</code><a href=\"__main__.py#L32\" class=\"source_link\" style=\"float:right\">[source]</a></h4>\n",
+       "<h4 id=\"TypeDispatch.__call__\" class=\"doc_header\"><code>TypeDispatch.__call__</code><a href=\"__main__.py#L33\" class=\"source_link\" style=\"float:right\">[source]</a></h4>\n",
        "\n",
        "> <code>TypeDispatch.__call__</code>(**\\*`args`**, **\\*\\*`kwargs`**)\n",
        "\n",
@@ -961,7 +964,7 @@
     {
      "data": {
       "text/markdown": [
-       "<h4 id=\"TypeDispatch.returns\" class=\"doc_header\"><code>TypeDispatch.returns</code><a href=\"__main__.py#L20\" class=\"source_link\" style=\"float:right\">[source]</a></h4>\n",
+       "<h4 id=\"TypeDispatch.returns\" class=\"doc_header\"><code>TypeDispatch.returns</code><a href=\"__main__.py#L21\" class=\"source_link\" style=\"float:right\">[source]</a></h4>\n",
        "\n",
        "> <code>TypeDispatch.returns</code>(**`x`**)\n",
        "\n",
@@ -1080,6 +1083,36 @@
     "test_eq(a2.f(()), (1,))"
    ]
   },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "#### Using TypeDispatch With Class Methods\n",
+    "\n",
+    "You can use `TypeDispatch` when defining class methods too:"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "def m_nin(cls, x:(str,numbers.Integral)): return str(x)+'1'\n",
+    "def m_bll(cls, x:bool): cls.foo='a'\n",
+    "def m_num(cls, x:numbers.Number): return x*2\n",
+    "\n",
+    "t = TypeDispatch([m_nin,m_num,m_bll])\n",
+    "class A: f = t # set class attribute `f` equal to a TypeDispatch\n",
+    "\n",
+    "test_eq(A.f(1), '11')  #dispatch to m_nin\n",
+    "test_eq(A.f(1.), 2.)   #dispatch to m_num\n",
+    "test_is(A.f.owner, A)\n",
+    "\n",
+    "A.f(False) # this triggers t.m_bll to run, which sets A.foo to 'a'\n",
+    "test_eq(A.foo, 'a')"
+   ]
+  },
   {
    "cell_type": "markdown",
    "metadata": {},
@@ -1396,6 +1429,7 @@
       "Converted 04_transform.ipynb.\n",
       "Converted 05_logargs.ipynb.\n",
       "Converted 06_meta.ipynb.\n",
+      "Converted 07_script.ipynb.\n",
       "Converted index.ipynb.\n"
      ]
     }