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digitalmars.D - Need size of rightmost array, not type...

reply Ary Manzana <ary esperanto.org.ar> writes:
This compiles fine:

----------------------------------------
template Foo() {
	const int Foo = 3;
}

void one() {
	int x = Foo!();
	char[] buf = new char[x];
}
----------------------------------------

However this:

----------------------------------------
template Foo() {
	const int Foo = 3;
}

void two() {
	char[] buf = new char[Foo!()];
}
----------------------------------------

main.d(6): need size of rightmost array, not type Foo!()

Why?
Feb 21 2007
parent reply Max Samukha <samukha voliacable.com> writes:
On Wed, 21 Feb 2007 23:59:21 -0300, Ary Manzana <ary esperanto.org.ar>
wrote:

This compiles fine:

----------------------------------------
template Foo() {
	const int Foo = 3;
}

void one() {
	int x = Foo!();
	char[] buf = new char[x];
}
----------------------------------------

However this:

----------------------------------------
template Foo() {
	const int Foo = 3;
}

void two() {
	char[] buf = new char[Foo!()];
}
----------------------------------------

main.d(6): need size of rightmost array, not type Foo!()

Why?

Seems to be a bug. If your array is not big, you might consider using a static array as the size is known at compile time. char[Foo!()] buf; works
Feb 22 2007
parent Ary Manzana <ary esperanto.org.ar> writes:
Max Samukha escribió:
 On Wed, 21 Feb 2007 23:59:21 -0300, Ary Manzana <ary esperanto.org.ar>
 wrote:
 
 This compiles fine:

 ----------------------------------------
 template Foo() {
 	const int Foo = 3;
 }

 void one() {
 	int x = Foo!();
 	char[] buf = new char[x];
 }
 ----------------------------------------

 However this:

 ----------------------------------------
 template Foo() {
 	const int Foo = 3;
 }

 void two() {
 	char[] buf = new char[Foo!()];
 }
 ----------------------------------------

 main.d(6): need size of rightmost array, not type Foo!()

 Why?

Seems to be a bug. If your array is not big, you might consider using a static array as the size is known at compile time. char[Foo!()] buf; works

Thanks Max. Walter: I don't know why this error appear. I was expecting it not to appear. I think the problem is the following functions: parser.c ############################################################# Expression *Parser::parseNewExp(Expression *thisexp) { // ... #if LTORARRAYDECL t = parseBasicType(); t = parseBasicType2(t); if (t->ty == Taarray) { Type *index = ((TypeAArray *)t)->index; Expression *e = index->toExpression(); if (e) { arguments = new Expressions(); arguments->push(e); t = new TypeDArray(t->next); } else { error("need size of rightmost array, not type %s", index->toChars()); return new NullExp(loc); } } } ####################################################### It seems e is null. However for the source code I gave, I think index is an instance of TypeIdentifier, so it is converted to a DotIdExp: mtype.c ####################################################### Expression *TypeIdentifier::toExpression() { Expression *e = new IdentifierExp(loc, ident); for (int i = 0; i < idents.dim; i++) { Identifier *id = (Identifier *)idents.data[i]; e = new DotIdExp(loc, e, id); } return e; } ####################################################### So: 1. I don't understand why e is null. Maybe index is not an instance of TypeIdentifier, but I think it is. 2. I think that function TypeIdentifier::toExpression() is incorrect. It is turning a type like "Foo!(a, b)" into an expression "Foo.a.b"... or am I misunderstanding something?
Feb 22 2007