On Thursday, 15 May 2014 at 12:16:52 UTC, Steven Schveighoffer
wrote:
On Thu, 15 May 2014 02:05:08 -0400, monarch_dodra
<[email protected]> wrote:
"move" will also delegate to "proxyMove".
This is the correct solution IMO. The principle of least
surprise should dictate that a.foo should always mean the same
thing. All that is required to enforce this is to make the
"hook" function have a different name.
The issue(s) I have with the "hook must have a different name" is:
1. In the algorithm implementation, you must explicitly test for
the hook, which, if we want to expand on, would turn all our
algorithms into:
void foo(T)(T t)
{
static if (is(typeof(t.fooHook())))
return t.fooHook();
else
...
}
2. The "overriden" hook is only useful if you import the
corresponding algorithm. So for example, in my 3rd pary library,
if my type has "findHook", I'd *have* to import
std.algorithm.find for it to be useful. Unless I want to make a
direct call to "findHook", which would be ugly...
An example for "2" are range primitives:
I think the two mechanisms of overriding default behavior:
1. Use a hook, to define the basic minimum functionality.
2. Implement the same-named method, but you must implement ALL
functionality (possibly deferring to the global function if
necessary).
-Steve
Also: "moveFront"/"moveBack" are other examples of such "globally
hijack-able" functions.
