On 16/Sep/10 8:49 PM, Stas Malyshev wrote:
No, we can't have python decorators because unlike Python PHP functions
and classes aren't first-class objects. In Python, this:
@dec2
@dec1
def func(arg1, arg2, ...):
pass
means this:
def func(arg1, arg2, ...):
pass
func = dec2(dec1(func))
However, you can't write equivalent code in PHP.
I had the same idea regarding decorators, and I saw the same problem
that you see, functions are not first-class citizens in PHP. I was
wondering, though, whether the possibility to assign expressions to
constants couldn't change that. Let me explain a little what I'm
thinking exactly.
Currently, PHP supports lambda expressions and they're pretty much as
first-class citizens as possible. PHP, also supports variable functions
in an attempt to make global functions look like they'd be first-class
citizens.
So, the following snippet isn't yet working, but AFAIK it will work in
the next PHP release:
function foo() {
echo "foo was called";
}
function bar() {
return 'foo';
}
bar()(); // prints "foo was called";
Now, assume I define this constant:
define('foo', 'foo');
Now I can write:
function bar() {
return foo;
}
And the "foo" function will look more like a first-class citizens.
But, how about being able to write:
const foo = function () use ($globalVar) {
};
which would be the desugaring of:
function foo () {
global $globalVar;
}
Now foo would be an instance of Closure, and would allow us to pass it
around free.
Does that make any sense to any of you? Is it at least possible with the
current Zend Engine implementation? What problems would it pose?
Getting back to decorators...
Having the above syntax, we would be able to write:
const func = dec2(dec1(function () {
}));
which can be further sugared to some decorator specific syntax.
I guess the gist of my whole email is that it would be nice to get rid
of the dollar sign in identifiers that designate lambda expressions.
That would somehow level things up.
--
Ionuț G. Stan | http://igstan.ro
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