Re: concepts v0.0.1

2016-12-19 Thread Atila Neves via Digitalmars-d-announce 
On Saturday, 17 December 2016 at 04:00:32 UTC, Nicholas Wilson 
wrote:
On Friday, 16 December 2016 at 23:49:18 UTC, Nicholas Wilson 
wrote:

On Friday, 16 December 2016 at 20:51:19 UTC, Atila Neves wrote:

@models!(Foo, isFoo)



What happened to the __UDA_ATTACHMENT__ proposal?


Nothing AFAIK.



Also are UDAs legal after the symbol? i.e. with 
__UDA_ATTACHMENT__ could you do struct Foo @models!isFoo

{
void foo();
}

 ?


Nope.

Re: concepts v0.0.1

2016-12-19 Thread Atila Neves via Digitalmars-d-announce 
On Saturday, 17 December 2016 at 14:58:24 UTC, Jacob Carlborg 
wrote:

On 2016-12-16 21:51, Atila Neves wrote:

[...]


It's not very well tested ;). When a check fails I get this 
error:


Oops!

Fixed it now. Look, now it's version 0.0.2! :P

Atila

Re: concepts v0.0.1

2016-12-17 Thread Jacob Carlborg via Digitalmars-d-announce 

On 2016-12-16 21:51, Atila Neves wrote:

Since my phobos PR for better static assertions was clearly never
getting merged (https://github.com/dlang/phobos/pull/3677), I moved the
code to dub instead:

http://code.dlang.org/packages/concepts

Basically, as long as you pair up your template constraints (e.g. isFoo)
with a suitably named function that should compile (e.g. checkFoo, not a
lambda), then you can write this:

@models!(Foo, isFoo)
struct Foo {
//...
}

And in the case that isFoo is false, you'll get to know _why_ it didn't
compile instead of an AssertError that leaves you confused.

At least it used to and the unit tests pass so I'm assuming it still
does :P


It's not very well tested ;). When a check fails I get this error:

Error: can only import from a module, not from package 
std.algorithm.searching.countUntil


After fixing that to a proper selective import I get:

Error: template instance moduleName!P template 'moduleName' is not defined

Adding an import for std.traits will fix that. Then after fixing all 
that it seems to work properly :)


Asserting that something does not compile is very risky because it does 
not tell you why it didn't compile. One should always first compile 
without __traits(compiles) to verify that the correct error is reported.


--
/Jacob Carlborg

Re: concepts v0.0.1

2016-12-16 Thread Nicholas Wilson via Digitalmars-d-announce 
On Friday, 16 December 2016 at 23:49:18 UTC, Nicholas Wilson 
wrote:

On Friday, 16 December 2016 at 20:51:19 UTC, Atila Neves wrote:

@models!(Foo, isFoo)



What happened to the __UDA_ATTACHMENT__ proposal?


Also are UDAs legal after the symbol? i.e. with 
__UDA_ATTACHMENT__ could you do struct Foo @models!isFoo

{
void foo();
}

 ?

Re: concepts v0.0.1

2016-12-16 Thread Nicholas Wilson via Digitalmars-d-announce 

On Friday, 16 December 2016 at 20:51:19 UTC, Atila Neves wrote:

@models!(Foo, isFoo)



What happened to the __UDA_ATTACHMENT__ proposal?

Re: concepts v0.0.1

2016-12-16 Thread Nordlöw via Digitalmars-d-announce 

On Friday, 16 December 2016 at 20:51:19 UTC, Atila Neves wrote:

Atila


Surprisingly little code. Thx.

concepts v0.0.1

2016-12-16 Thread Atila Neves via Digitalmars-d-announce 
Since my phobos PR for better static assertions was clearly never 
getting merged (https://github.com/dlang/phobos/pull/3677), I 
moved the code to dub instead:


http://code.dlang.org/packages/concepts

Basically, as long as you pair up your template constraints (e.g. 
isFoo) with a suitably named function that should compile (e.g. 
checkFoo, not a lambda), then you can write this:


@models!(Foo, isFoo)
struct Foo {
//...
}

And in the case that isFoo is false, you'll get to know _why_ it 
didn't compile instead of an AssertError that leaves you confused.


At least it used to and the unit tests pass so I'm assuming it 
still does :P


Atila