mixin templates with name parameter
js.mdnq
js_adddot+mdng at gmail.com
Thu Nov 29 17:08:16 PST 2012
mixin templates seems like they could benefit from an extra
parameter that one can pass a name. The name, a string literal,
sort of acts like a preprocessor token:
mixin template InjectX!(T)
{
private T x;
T get#name#( ) { return x; }
void set#name#(T y)
{
// Checks
x = y;
}
}
Then something like "mixin InjectX!int Mylnt;" will create the
following function
getMylnt and setMylnt.
The scope names are a nice solution and sometimes what one wants.
But sometimes one would like to avoid an extra referencing step.
In fact, it would be nice if one could inject code into the
template code. One, could example, even supply an object or
another mixin with the mixin to compose the code. If, say, I
wanted slightly different set functions above I would have to
write a template for each one, but if I code compose mixins then
I could avoid that.
In any case, it can get rather complicated and notation is the
key issue(how to describe it all elegantly). I think the idea and
the way D does it is pretty elegant though and probably good
enough for most cases. I just imagine cases where a very complex
mixin might need slight changes from one use to the next but
unfortunately would require some inelegant methods to use it.
Possibly one could compose mixins in a way that all common
function overlap are serialized.
"alias mixin InjectX!int with InjectY!int Mylntalias;"
"mixin MyIntalias!int MyInt;"
will produce a mixin s.t., the set functions of Y are serialized
with those of X. (the new set function will first call the set of
InjectY then that of InjectX)
This way, we can "extend" a mixin relatively easy by simply
"appending" code to it's functions.
Just some food for thought.
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