• DLearner (30/30) May 31 2014 Hi,
• Adam D. Ruppe (4/5) May 31 2014 Yes, nested functions access local variables and thus follow the
• Philippe Sigaud via Digitalmars-d-learn (3/3) May 31 2014 See: http://dlang.org/function.html#variadicnested
• Jonathan M Davis via Digitalmars-d-learn (12/42) Jun 01 2014 On Sat, 31 May 2014 16:18:33 +0000

"DLearner" <bmqazwsx123 gmail.com> writes:

Hi,

import std.stdio;
void main() {

    writefln("Entered");

    sub1();
    sub1();
    sub1();

    writefln("Returning");

    void sub1() {
       static int i2 = 6;

       i2 = i2 + 1;
       writefln("%s",i2);
    };
}

does not compile, but

import std.stdio;
void main() {
    void sub1() {
       static int i2 = 6;

       i2 = i2 + 1;
       writefln("%s",i2);
    };
    writefln("Entered");

    sub1();
    sub1();
    sub1();

    writefln("Returning");


}

compiles and runs as expected.

Is this intended?

"Adam D. Ruppe" <destructionator gmail.com> writes:

On Saturday, 31 May 2014 at 16:18:35 UTC, DLearner wrote:
 Is this intended?

Yes, nested functions access local variables and thus follow the 
same order of declaration rules as they do; you can't use a local 
variable before it is declared so same with a nested function.

Philippe Sigaud via Digitalmars-d-learn writes:

See:  http://dlang.org/function.html#variadicnested

The second example explains that nested functions can be accessed only
if the name is in scope.

Jonathan M Davis via Digitalmars-d-learn writes:

On Sat, 31 May 2014 16:18:33 +0000
DLearner via Digitalmars-d-learn <digitalmars-d-learn puremagic.com>
wrote:

 Hi,

 import std.stdio;
 void main() {

     writefln("Entered");

     sub1();
     sub1();
     sub1();

     writefln("Returning");

     void sub1() {
        static int i2 = 6;

        i2 = i2 + 1;
        writefln("%s",i2);
     };
 }

 does not compile, but

 import std.stdio;
 void main() {
     void sub1() {
        static int i2 = 6;

        i2 = i2 + 1;
        writefln("%s",i2);
     };
     writefln("Entered");

     sub1();
     sub1();
     sub1();

     writefln("Returning");


 }

 compiles and runs as expected.

 Is this intended?

Currently, you cannot forward reference a nested function. Kenji was looking
into it recently, so maybe we'll be able to at some point in the future, but
right now, we definitely can't. But even if we can in the future, I'd expect
that you'd have to declare a prototype for the function to be able to use it
before it's declared. In general though, I think that the only reason that it
would really be useful would be to have two nested functions refer to each
other, since otherwise, you just declare the nested function earlier in the
function.

- Jonathan M Davis