The implementation of the GOAL type system with Racket language. This explanation of the GOAL type system available here Or you can see the source code of whole Jack Project
I plan to write a GOAL compiler as an embedded solution in mobile applications or game engines. The compiler is incomplete at the moment, but the type system is ready.
The plan was to use Racket because of its system of Syntax objects. The input .gc file can be parsed with read-syntax and the resulting Syntax object tree can be transformed to AST and then the code can be compiled.
Syntax tree advantage over s-expression is that Syntax-tree has information about position of Syntax-object in source file. Thus error information may contain necessary debugging information.
It is mostly works, the test code in deftype.rkt file parsing the file all-types.gc with 34k lines of code. As result it is defining 1539 types and 89 enums. For a futue development reuired only a bugfixing and making better error messaging with Racket exeptions handling and Syntax locations.
- interfaces.rkt -- Interface for all types
- type.rkt -- The base type for all types
- basic-types.rkt -- All avaibale types: field, null, struct, value, bitfield, enum
- type-spec.rkt -- The universal type reference aka '(function (int int int))'
- state.rkt -- The state type functions
- type-system.rkt -- The main type system
- builting-types.rkt -- Initializer of type system by builting types
- defenum.rkt -- The enum expression parser
- deftype.rkt -- The deftype expression parser
- rt-type.rkt -- The runtime version of basic type. Not used by type system above
- goalc-all-types.gc -- The list of typespecs of the GOAL
- goalc-type-specs.txt -- The GOAL types file used for testing
The peculiarity of the implementation is that it is maximally identical to the OpenGOAL project. Parsers get a list of syntax without the first element as an argument. That is, for defenum statement the list starts with the name of the new type, but the keyword defenum is omitted.
;; Define new type system and add builtin types
(define tsys (type-system-new!))
;; Parse statements
(parse-declare-type the-declare-type-syntax-list tsys)
(parse-deftype the-deftype-syntax-list tsys constants)
(parse-defenum the-defenum-syntax-list tsys)