On Sunday, 4 October 2015 at 19:12:51 UTC, Laeeth Isharc wrote:
On Sunday, 4 October 2015 at 18:24:08 UTC, John Colvin wrote:
On Sunday, 4 October 2015 at 18:08:55 UTC, Laeeth Isharc wrote:
On Sunday, 4 October 2015 at 17:17:14 UTC, Laeeth Isharc
wrote:
On Sunday, 4 October 2015 at 16:37:34 UTC, John Colvin wrote:
On Sunday, 4 October 2015 at 15:45:55 UTC, Laeeth Isharc
wrote:
How do I persuade partial to tie itself to the appropriate
overload?
---
As far as I can see std.functional.partial only does one
argument at a time.
bars=partial!(partial!(partial!(slurpBars!BarType,
filename), startDate), endDate);
or maybe, I'm not sure, but maybe you can do:
bars=partial!(slurpBars!BarType, AliasSeq!(filename,
startDate, endDate));
If you find you really need to manually mess with
overloads, use http://dlang.org/traits.html#getOverloads.
You may have to wrap it in AliasSeq in some situations due
to grammar/parser constraints.
fwiw - still doesn't work (whether I use alias or auto,
trying each of your solutions). I'll look at getOverloads.
How do I distinguish between two overloads that return the
same type but have different arguments? It looks like
getOverloads only deals with cases where the return type is
different, judging by the docs.
getOverloads should give you all the overloads of a function,
whether they return the same or different types. The example
in the docs just happens to have different types.
In general, return types are not considered when talking about
overloads. For example, two functions that take the same
arguments but have different return types are not overloaded,
they are in conflict.
Thanks for this. The only problem then is how to manipulate
what getOverloads returns. (No need to do this now as it's not
worth it - I just wanted to try using partial if it wasn't too
much work. easier just to make an alternate declaration with
the type in its name).
Is this not a bug in the implementation of partial?
import std.functional;
import std.stdio;
void bish(T)(string arg, string barg)
{
writefln("bishs: %s, %s",arg,barg,to!T);
}
void bish(T)(int argi, string barg)
{
writefln("bishi: %s, %s",argi,barg.to!T);
}
void main(string[] args)
{
alias b=partial!(bish!string,"hello"); // this line does not
compile
alias c=partial!(b,"therex");
b("there");
c();
}
[laeeth@engine marketdata]$ dmd partial.d
partial.d(15): Error: template partial.bish matches more than
one template declaration:
partial.d(4): bish(T)(string arg, string barg)
and
partial.d(8): bish(T)(int argi, string barg)
partial knows which overload to call - I told it!
The problem happens before partial. Something like
alias b = bish!string;
is an error, because it matches both templates. For some reason
if you call it directly, e.g.
bish!string("","");
that's ok, but I have no idea why.
What you can do, is this:
template bish(T)
{
void bish(string arg, string barg)
{
writefln("bishs: %s, %s",arg,barg.to!T);
}
void bish(int argi, string barg)
{
writefln("bishi: %s, %s",argi,barg.to!T);
}
}
which is just a template containing an overload set, which is no
problem.
Or:
void bish0(T)(string arg, string barg)
{
writefln("bishs: %s, %s",arg,barg.to!T);
}
void bish1(T)(int argi, string barg)
{
writefln("bishi: %s, %s",argi,barg.to!T);
}
alias bishStr = bish0!string;
alias bishStr = bish1!string;
void main(string[] args)
{
alias b=partial!(bishStr,"hello");
alias c=partial!(b,"therex");
b("there");
c();
}
Or:
void bish0(T)(string arg, string barg)
{
writefln("bishs: %s, %s",arg,barg.to!T);
}
void bish1(T)(int argi, string barg)
{
writefln("bishi: %s, %s",argi,barg.to!T);
}
template bish(T)
{
alias tmp = bish0!T;
alias tmp = bish1!T;
alias bish = tmp;
}
void main(string[] args)
{
alias b=partial!(bish!string, "hello");
alias c=partial!(b,"therex");
b("there");
c();
}
