gcc/d/dmd/nspace.d

   1 /**
   2  * A scoped C++ namespace symbol
   3  *
   4  * D supports the following syntax to declare symbol(s) as being part of a
   5  * C++ namespace:
   6  * ---
   7  * extern (C++, "myNamespace") { /+ Symbols +/ }       // String variant
   8  * extern (C++, SomeNamespace) { /+ Other symbols +/ } // Identifier variant
   9  * ---
  10  * The first form is an attribute and only affects mangling, and is implemented
  11  * in `dmd.attrib`.
  12  * The second form introduces a named scope and allows symbols to be refered
  13  * to with or without the namespace name, much like a named template mixin,
  14  * and is implemented in this module.
  15  * ---
  16  * extern (C++, Basket)
  17  * {
  18  *     struct StrawBerry;
  19  *     void swapFood (Strawberry* f1, Strawberry* f2);
  20  * }
  21  * void main ()
  22  * {
  23  *     Basket.StrawBerry fruit1;
  24  *     StrawBerry fruit2;
  25  *     Basket.swapFood(fruit1, fruit2);
  26  *     swapFood(fruit1, fruit2);
  27  * }
  28  * ---
  29  * Hence the `Nspace` symbol implements the usual `ScopeDsymbol` semantics.
  30  *
  31  * Note that it implies `extern(C++)` so it cannot be used as a generic
  32  * named scope. Additionally, `Nspace` with the same `Identifier` can be
  33  * defined in different module (as C++ allows a namespace to be spread accross
  34  * translation units), but symbols in it should be considered
  35  * part of the same scope. Lastly, not all possible C++ namespace names
  36  * are valid D identifier.
  37  *
  38  * See_Also:    https://github.com/dlang/dmd/pull/10031
  39  * Copyright:   Copyright (C) 1999-2024 by The D Language Foundation, All Rights Reserved
  40  * Authors:     $(LINK2 https://www.digitalmars.com, Walter Bright)
  41  * License:     $(LINK2 https://www.boost.org/LICENSE_1_0.txt, Boost License 1.0)
  42  * Source:      $(LINK2 https://github.com/dlang/dmd/blob/master/src/dmd/nspace.d, _nspace.d)
  43  * Documentation:  https://dlang.org/phobos/dmd_nspace.html
  44  * Coverage:    https://codecov.io/gh/dlang/dmd/src/master/src/dmd/nspace.d
  45  */
  46
  47 module dmd.nspace;
  48
  49 import dmd.arraytypes;
  50 import dmd.dsymbol;
  51 import dmd.expression;
  52 import dmd.identifier;
  53 import dmd.location;
  54 import dmd.visitor;
  55 import core.stdc.stdio;
  56
  57 /// Ditto
  58 extern (C++) final class Nspace : ScopeDsymbol
  59 {
  60     /**
  61      * Namespace identifier resolved during semantic.
  62      */
  63     Expression identExp;
  64
  65     extern (D) this(const ref Loc loc, Identifier ident, Expression identExp, Dsymbols* members)
  66     {
  67         super(loc, ident);
  68         //printf("Nspace::Nspace(ident = %s)\n", ident.toChars());
  69         this.members = members;
  70         this.identExp = identExp;
  71     }
  72
  73     override Nspace syntaxCopy(Dsymbol s)
  74     {
  75         auto ns = new Nspace(loc, ident, identExp, null);
  76         ScopeDsymbol.syntaxCopy(ns);
  77         return ns;
  78     }
  79
  80     override bool hasPointers()
  81     {
  82         //printf("Nspace::hasPointers() %s\n", toChars());
  83         return members.foreachDsymbol( (s) { return s.hasPointers(); } ) != 0;
  84     }
  85
  86     override const(char)* kind() const
  87     {
  88         return "namespace";
  89     }
  90
  91     override inout(Nspace) isNspace() inout
  92     {
  93         return this;
  94     }
  95
  96     override void accept(Visitor v)
  97     {
  98         v.visit(this);
  99     }
 100 }