jerry quinn wrote:
Christopher Wright Wrote:
jerry quinn wrote:
Hi there,
I'm not sure if I'm missing something, but I'm having trouble seeing that a
simple declaration will parse correctly with the D grammar.
If we take a declaration statment like:
int x = 3;
we have (my best guess):
DeclarationStatement -> Declaration
Declaration -> Decl
Decl -> BasicType Declarators ;
BasicType -> int
Declarators -> DeclaratorInitializer
DeclaratorInitializer -> Declarator = Initializer
Declarator -> BasicType2 Identifier
BasicType2 -> ????
I'm thinking that BasicType2 is optional here, rather than required as the
grammar shows. Is that correct?
Thanks
Jerry
. Declaration -> Decl
. Decl -> BasicType Declarators
. BasicType -> "int"
. Declarators -> DeclaratorInitializer
. DeclaratorInitializer -> Declarator "=" Initializer
We agree up to here.
. Declarator -> Identifier
Here, you don't need BasicType2, and if you use it, you recurse, so
using the rule Declarator -> BasicType2 Declarator here is useless.
What you describe sounds like what I'd expect.
Maybe I'm missing something. The grammar shown in
http://www.digitalmars.com/d/2.0/declaration.html has the following rules:
BasicType2:
*
[ ]
[ Expression ]
[ Expression .. Expression ]
[ Type ]
delegate Parameters FunctionAttributesopt
function Parameters FunctionAttributesopt
Declarator:
BasicType2 Declarator DeclaratorSuffixesopt
BasicType2 Identifier DeclaratorSuffixesopt
With this definition, I don't see how you can get Declarator->Identifier.
Jerry
You are correct. BasicType2 can match nothing. It should also be able to
match what it does above multiple times.
