On 2014-10-18 21:52:30 +0000, Shammah Chancellor said:
On 2014-10-15 17:29:33 +0000, Trass3r said:
http://youtu.be/qwXq5MqY2ZA?t=33m57s
I wish we had diagnostics like that in D.
I have answered your call:
https://github.com/D-Programming-Language/phobos/pull/2627
Please comment.
-S.
I don't know if anyone looked at this yet, but I've updated it quite a
bit since the original post. Please take a look again and comment.
It also generates some useful DDoc now.
Docs:
bool isConcept(T, C, bool diagnostics = false, string errorPrefix = "")();
Returns true if T supports the concept C. Note, templated member
functions are not supported currently.
Concepts should be defined as in the following example:
----
class CInputRange(E) : Concept
{
abstract void popFront();
@property abstract E front();
bool empty;
//Optional Axioms function. This will be checked if it compiles, and
that it returns true if it does.
static bool Axioms(T)()
{
return true;
}
}
class CInfinite() : Concept
{
static bool Axioms(T)() {
enum empty = T.empty;
return !empty;
}
}
class CInfiniteInputRange(E) : CInputRange!E
{
mixin CInfinite;
}
---
template conceptDiagnostic(R, string F, int L, C...)
Prints error messages for why template instantiation failed.
Examples:
---
bool DoStuff(R)(R infRange) if ( isConcept!(R, CInfiniteInputRange!string))
{
return true;
}
bool DoStuff(R)(R infRange) if ( isConcept!(R, COutputRange!string))
{
return true;
}
//Example of using conceptDiagnostic
bool DoStuff(R, string F = __FILE__, size_t L = __LINE__ )(R infRange)
{
mixin conceptDiagnostic!(R, F, L, COutputRange!string,
CInfiniteInputRange!string);
return false;
}
---
class Concept;
Base class for Concepts. All Concepts should derive from this, or
another concept.
