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digitalmars.D - Looking for Details On Recent Changes

reply Xinok <xnknet gmail.com> writes:
I'm looking for details on two changes in particular.

First comes from 1.011, being the macro keyword. I can't find anything 
about it, and I have no idea how to use it.

Second comes from 1.010:

 Added template partial specialization derived from multiple parameters.




I don't understand what this means exactly?
Apr 11 2007
next sibling parent reply Dan <murpsoft hotmail.com> writes:
Xinok Wrote:


 I'm looking for details on two changes in particular.
 
 First comes from 1.011, being the macro keyword. I can't find anything 
 about it, and I have no idea how to use it.
 
 Second comes from 1.010:
  >> Added template partial specialization derived from multiple parameters.
 I don't understand what this means exactly?


Aww shit.  D's getting macros?  I was hoping to avoid having to read those.

and... wow.  let me get my dictionary.
Apr 11 2007
parent Chris Nicholson-Sauls <ibisbasenji gmail.com> writes:
Dan wrote:

 Xinok Wrote:
 

 I'm looking for details on two changes in particular.

 First comes from 1.011, being the macro keyword. I can't find anything 
 about it, and I have no idea how to use it.

 Second comes from 1.010:
  >> Added template partial specialization derived from multiple parameters.
 I don't understand what this means exactly?


 
 Aww shit.  D's getting macros?  I was hoping to avoid having to read those.


Yes macros, but nothing like C pre-processor macros.  No #DEFINE's in sight. 
From the 
prior discussions on this, they will appear something more like this:

macro default_gettor (name, var) {
   typeof(var) name () { return var; }
}

class Foo {
   private int _bar ;

   this (int barval) { _bar = barval; }

   default_gettor(bar, _bar);
}

Contrived example, but you get the notion of what it will make possible. 
Presumably they 
could also be used with Tuples via a wrapping template... which means you could
write a 
template-macro pair that cough up an entire module for, say, a variant type
with some 
simple introspection capabilities, which can have new types/behaviors added to
it just by 
adding one relatively simple line to a macro call or template instantiation at
the bottom 
of the module.  (At least, that's a rough description of something I plan to do
with them.)

-- Chris Nicholson-Sauls
Apr 11 2007
prev sibling next sibling parent Don Clugston <dac nospam.com.au> writes:
Xinok wrote:

 I'm looking for details on two changes in particular.
 
 First comes from 1.011, being the macro keyword. I can't find anything 
 about it, and I have no idea how to use it.


Right now, it does nothing except gives an error if you try to use it.
Like 'cent'.


 Second comes from 1.010:
  >> Added template partial specialization derived from multiple parameters.
 I don't understand what this means exactly?
Apr 11 2007
prev sibling parent =?ISO-8859-1?Q?Jari-Matti_M=E4kel=E4?= <jmjmak utu.fi.invalid> writes:
Xinok wrote:

 I'm looking for details on two changes in particular.
 
 First comes from 1.011, being the macro keyword. I can't find anything
 about it, and I have no idea how to use it.


It has been just reserved now. It will do something in the (near) future.


 Second comes from 1.010:

 Added template partial specialization derived from multiple parameters.




 I don't understand what this means exactly?


There's an example about it on the template page.
http://digitalmars.com/d/template.html

  Deduction from a specialization can provide values for more than one
  parameter:

  template Foo(T: T[U], U)
  {
      ...
  }

  Foo!(int[long])  // instantiates Foo with T set to int, U set to long

Although I also had to diff those docs to find it.
Apr 11 2007