Christopher J. Bottaro wrote:
> I haven't tried it yet, but this is what I would do with __call():
>
> function __call($name, $args) {
> $name .= 'IMPL';
> try { $this->$name($args); }
> except { # error handling; }
> }
>
> function funcA() {
> # do something
> }
>
> function funcBIMPL($a, $b) {
> # do something
> }
>
> So I imagine it would work like this:
>
> $obj = new MyClass();
> $obj->funcA(); # actually calls funcA because the function
> # exists in the class
> $obj->funcB($a, $b); # funcB doesn't exist, so __call() gets called with
> # args 'funcB', array($a, $b)
> # so inside __call(), we append 'IMPL' to $name, then invoke
> # $this->funcBIMPL($a, $b)
>
> Using this setup, when I want to add a new function called mySuperFunc(), I
> merely have to define mySuperFuncIMPL() and magically the wrapper is "made
> for me"...=)
Something like this might work:
py> class C(object):
... def func_a(self):
... print "func_a"
... def func_b_impl(self):
... print "func_b"
... raise Exception
... def __getattr__(self, name):
... func = getattr(self, '%s_impl' % name)
... wrapped_func = self._impl_wrapper(func)
... setattr(self, name, wrapped_func)
... return wrapped_func
... def _impl_wrapper(self, func):
... def wrapper(*args, **kwargs):
... try:
... return func(*args, **kwargs)
... except:
... print "entered except"
... raise
... return wrapper
...
py> c = C()
py> c.func_a()
func_a
py> c.func_b()
func_b
entered except
Traceback (most recent call last):
File "<interactive input>", line 1, in ?
File "<interactive input>", line 15, in wrapper
File "<interactive input>", line 6, in func_b_impl
Exception
The idea here is that __getattr__ is called whenever the class doesn't
have a particular function. The __getattr__ method then tries to find a
corresponding _impl function, wraps it with appropriate try/except code,
and returns the wrapped function.
HTH,
STeVe
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