From 93654e5246f1b9ecf3e55ea04e9cc0b7e5c9825a Mon Sep 17 00:00:00 2001
From: Thomas Leonard <talex5@gmail.com>
Date: Sun, 7 Sep 2008 17:01:23 +0100
Subject: [PATCH] Passes arguments to Main constructor

Each argument is created by calling _externals.ARG() in the
generated main() function.
---
 dmd/idgen.c  |  1 +
 dmd/module.c | 84 +++++++++++++++++++++++++++++++++++++++++++++---------------
 2 files changed, 65 insertions(+), 20 deletions(-)

diff --git a/dmd/idgen.c b/dmd/idgen.c
index 7d882b4..6a0ce7e 100644
--- a/dmd/idgen.c
+++ b/dmd/idgen.c
@@ -211,6 +211,7 @@ struct Msgtable msgtable[] =
     { "aaKeys", "_aaKeys" },
     { "aaValues", "_aaValues" },
     { "aaRehash", "_aaRehash" },
+    { "_externals" },
     { "args" },
 
     // For pragma's
diff --git a/dmd/module.c b/dmd/module.c
index 46728a9..449697f 100644
--- a/dmd/module.c
+++ b/dmd/module.c
@@ -649,34 +649,73 @@ void Module::parse()
 }
 
 FuncDeclaration *addMainFunction(Dsymbol *mainClass) {
-	ClassDeclaration *klass = mainClass->isClassDeclaration();
-	if (klass == NULL) {
-		// Just ignore it then?
-		error("'Main' is not a class!");
-	}
+    ClassDeclaration *klass = mainClass->isClassDeclaration();
+    if (klass == NULL) {
+	// Just ignore it then?
+	error("'Main' is not a class!");
+    }
 
-	// Create a main(string[] args) function
-	Arguments *arguments = new Arguments();
+    // Create a main(string[] args) function
+    Arguments *arguments = new Arguments();
 
-	Type *tstr = new TypeDArray(Type::tchar);
-	Type *targv = new TypeDArray(tstr);
+    Type *tstr = new TypeDArray(Type::tchar);
+    Type *targv = new TypeDArray(tstr);
 
-	Argument *a = new Argument(STCin, targv, Id::args, NULL);
-	arguments->push(a);
+    Argument *a = new Argument(STCin, targv, Id::args, NULL);
+    arguments->push(a);
 
-	Loc loc = mainClass->loc;
+    Loc loc = mainClass->loc;
 
-	TypeFunction *ta = new TypeFunction(arguments, new Type(Tvoid, NULL), 0, LINKc);
-	FuncDeclaration *f = new FuncDeclaration(mainClass->loc, 0, Id::main, STCundefined, ta);
+    TypeFunction *ta = new TypeFunction(arguments, new Type(Tvoid, NULL), 0, LINKc);
+    FuncDeclaration *f = new FuncDeclaration(mainClass->loc, 0, Id::main, STCundefined, ta);
 
-	// Inside main(), create a new Main
+    // Find the constructor
+    CtorDeclaration *ctor = NULL;
+    for (int i = 0; i < klass->members->dim; i++) {
+	Dsymbol *s;
 
-	f->endloc = mainClass->loc;
-	NewExp *e = new NewExp(loc, NULL, NULL, klass->getType(), NULL);
-	Statement *s = new ExpStatement(loc, e);
-	f->fbody = s;
+	s = (Dsymbol *)klass->members->data[i];
+	CtorDeclaration *thisCtor = s->isCtorDeclaration();
+	if (thisCtor) {
+	    if (ctor) {
+		error(thisCtor->loc, "Multiple constructors for Main class!");
+		return NULL;
+	    } else {
+		ctor = thisCtor;
+	    }
+	}
+    }
 
-	return f;
+    Expressions *args = new Expressions();
+
+    if (ctor == NULL) {
+	f->endloc = klass->loc;	// Use default constructor
+    } else {
+	f->endloc = ctor->loc;
+
+	Expressions *builderArgs = new Expressions();
+	Expression *externals = new IdentifierExp(ctor->loc, Id::_externals);
+	// Collect all the objects we need for the constructor's arguments
+	for (int i = 0; i < ctor->arguments->dim; i++) {
+	    Argument *arg = (Argument *) ctor->arguments->data[i];
+	    Expression *builder = new DotIdExp(ctor->loc, externals, arg->ident);
+	    args->push(new CallExp(ctor->loc, builder, builderArgs));
+	    /*
+	    error(ctor->loc,
+		    "Don't know how to provide a '%s' to the Main constructor",
+		    arg->ident->toChars());
+	    return NULL;
+	    */
+	}
+    }
+
+    // Inside main(), create a new Main
+
+    NewExp *e = new NewExp(loc, NULL, NULL, klass->getType(), args);
+    Statement *s = new ExpStatement(loc, e);
+    f->fbody = s;
+
+    return f;
 }
 
 void Module::semantic()
@@ -730,7 +769,12 @@ void Module::semantic()
 
 	if (s->ident && s->ident == Id::Main) {
 	    Dsymbol *mainFn = addMainFunction(s);
+	    if (!mainFn)
+		return;
 	    members->push(mainFn);
+
+	    Import *im = new Import(0, NULL, Id::_externals, NULL, true);
+	    members->shift(im);
 	    break;
 	}
     }
-- 
2.11.4.GIT