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digitalmars.D - Use UDAs for GDC attributes

reply "jerro" <a a.com> writes:
I think it would be a good idea to replace GDC's pragma attribute 
with UDAs. I I have an implementation of this at 
https://github.com/jerro/GDC/tree/uda-gcc-attributes. The API 
consists of a module named gcc.attribute that contains a function 
template attribute():

auto attribute(A...)(A args) if(A.length > 0 && is(A[0] == 
string))

This function is used like this:

import gcc.attribute;

 attribute("gdc_attribute_name", arg1, arg2) foo()
{
     ...
}

This adds an attribute gdc_attribute_name(arg, arg2) to foo and 
is equivalent to

pragma(attribute, gdc_attribute_name(arg1, arg2)) foo()
{
     ....
}

The advantage of using UDAs for GDC attributes is that you can 
alias them or use typetuples of attributes, possibly depending on 
the values of template parameters. One possible use case is this:

https://github.com/TurkeyMan/phobos/pull/3#issuecomment-11694942

Using UDAs for attributes would also enable us to remove a bunch 
of code that currently deals with GDC attributes from GDC's 
version of the frontend.

I'd like to hear your opinions and suggestions on this.
Feb 27 2013
parent reply Jacob Carlborg <doob me.com> writes:
On 2013-02-27 12:57, jerro wrote:

 I think it would be a good idea to replace GDC's pragma attribute with
 UDAs. I I have an implementation of this at
 https://github.com/jerro/GDC/tree/uda-gcc-attributes. The API consists
 of a module named gcc.attribute that contains a function template
 attribute():

 auto attribute(A...)(A args) if(A.length > 0 && is(A[0] == string))

 This function is used like this:

 import gcc.attribute;

  attribute("gdc_attribute_name", arg1, arg2) foo()
 {
      ...
 }

 This adds an attribute gdc_attribute_name(arg, arg2) to foo and is
 equivalent to

 pragma(attribute, gdc_attribute_name(arg1, arg2)) foo()
 {
      ....
 }

 The advantage of using UDAs for GDC attributes is that you can alias
 them or use typetuples of attributes, possibly depending on the values
 of template parameters. One possible use case is this:

 https://github.com/TurkeyMan/phobos/pull/3#issuecomment-11694942

 Using UDAs for attributes would also enable us to remove a bunch of code
 that currently deals with GDC attributes from GDC's version of the
 frontend.

 I'd like to hear your opinions and suggestions on this.


I think someone has already suggested this.

-- 
/Jacob Carlborg
Feb 27 2013
parent "jerro" <a a.com> writes:
 I think someone has already suggested this.


Sure, Iain has some time ago. Now I have an implementation and he 
told me to post it here for feedback.
Feb 27 2013