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digitalmars.D - Are out-of-class-declaration method definitions allowed?

reply "AJ" <aj nospam.net> writes:
   I can't imagine anyone that knows D doesn't also know C++, but the 
opposite is hardly true, so here's some valid C++ that I'm wondering if 
there is an equivalent style allowed in D:

class MyClass
{
  public:
   void DoIt();
};

void MyClass::DoIt()
{
    // do it
}

   (Aside: D has no 'inline' keyword, correct? And, should I post questions 
like this post in the learn group? Even if the potential is likely that a 
language design discussion may result?)
Nov 12 2009
next sibling parent Ellery Newcomer <ellery-newcomer utulsa.edu> writes:
AJ wrote:
    I can't imagine anyone that knows D doesn't also know C++, but the 
 opposite is hardly true, so here's some valid C++ that I'm wondering if 
 there is an equivalent style allowed in D:
 
 class MyClass
 {
   public:
    void DoIt();
 };
 
 void MyClass::DoIt()
 {
     // do it
 }
 
    (Aside: D has no 'inline' keyword, correct? And, should I post questions 
 like this post in the learn group? Even if the potential is likely that a 
 language design discussion may result?)
 
 

Nov 12 2009
prev sibling next sibling parent BCS <none anon.com> writes:
Hello aJ,

 I can't imagine anyone that knows D doesn't also know C++, but the
 opposite is hardly true, so here's some valid C++ that I'm wondering
 if there is an equivalent style allowed in D:
 
 class MyClass
 {
 public:
 void DoIt();
 };
 void MyClass::DoIt()
 {
 // do it
 }
 (Aside: D has no 'inline' keyword, correct? And, should I post
 questions like this post in the learn group? Even if the potential is
 likely that a language design discussion may result?)
 

AFAIK That is not supported. You can do it by declaring an extern(C) function named with whatever that method's name mangles to ... but why?
Nov 12 2009
prev sibling parent reply "Steven Schveighoffer" <schveiguy yahoo.com> writes:
On Thu, 12 Nov 2009 23:19:21 -0500, AJ <aj nospam.net> wrote:

    I can't imagine anyone that knows D doesn't also know C++, but the
 opposite is hardly true, so here's some valid C++ that I'm wondering if
 there is an equivalent style allowed in D:

 class MyClass
 {
   public:
    void DoIt();
 };

 void MyClass::DoIt()
 {
     // do it
 }

You can define MyClass in a .di file without implementations, and then rewrite it in the .d file with implementations. That's about as close as you can get.
    (Aside: D has no 'inline' keyword, correct? And, should I post  
 questions
 like this post in the learn group? Even if the potential is likely that a
 language design discussion may result?)

d.learn is probably the right place, though most people look at both. You'll get the occasional OCD post about how newbie questions really should be on d.learn, but it doesn't bother me :) inlining is done automatically by the compiler as long as it can see the entire function source and you pass the -inline command line switch to the compiler. The theory being -- the compiler probably knows better what things are good to inline. In practice, this sometimes isn't the case, but it's all we have to work with right now. -Steve
Nov 13 2009
parent bearophile <bearophileHUGS lycos.com> writes:
Steven Schveighoffer:

 The theory being -- the compiler probably knows better what things are  
 good to inline.  In practice, this sometimes isn't the case, but it's all  
 we have to work with right now.

In LDC there's a way to tell the compiler that a function that contains asm is suitable for inlining. In LDC there's also a compilation flag that accepts a number, that's the inlining threshold, you can use it to inline less or inline more. I think 97% of the times the LDC compiler is able to do a good enough job of inlining. I remember only two times where LDC has not inlined something in need to be inlined. In this situations I've had to use an ugly string mixin, to create a kind of C macro, to inline those things by hand... Bye, bearophile
Nov 13 2009