start sketching out type system

2 files changed, 51 insertions, 73 deletions

diff --git a/include/fwd/ast.h b/include/fwd/ast.h
index a253901..36aa8c8 100644
--- a/include/fwd/ast.h
+++ b/include/fwd/ast.h
@@ -56,8 +56,18 @@ struct type {
 
 /** Possible AST node types. We reserve node 0 as an illegal value. */
 enum ast_kind {
-	/** Creating new variable. */
-	AST_LET = 1,
+	/** Trait definition */
+	AST_TRAIT_DEF = 1,
+	/** Trait application */
+	AST_TRAIT_APPLY,
+	/** Structure definition */
+	AST_STRUCT_DEF,
+	/** Structure continuation */
+	AST_STRUCT_CONT,
+	/** Import */
+	AST_IMPORT,
+	/** Creating new variable */
+	AST_LET,
 	/** If statement */
 	AST_IF,
 	/** Nil check */
@@ -141,6 +151,7 @@ enum ast_flag {
 	AST_FLAG_ANALYZED       = (1 << 0),
 	AST_FLAG_PREANALYZIS    = (1 << 1),
 	AST_FLAG_NOMOVES        = (1 << 2),
+	AST_FLAG_PUBLIC		= (1 << 3),
 };
 
 struct ast {
@@ -161,6 +172,8 @@ struct ast {
 	struct type *t;
 	enum ast_flag flags;
 
+	struct ast *chain;
+
 	/* optional group */
 	struct ast *ol;
 	struct ast *or;
@@ -412,6 +425,31 @@ static inline bool is_trivially_copyable(struct type *type)
 #define gen_block(body, err, loc) \
 	gen2(AST_BLOCK, body, err, loc)
 
+#define trait_id(x) return_s(x, AST_TRAIT_DEF)
+#define trait_body(x) return_a1(x, AST_TRAIT_DEF)
+#define gen_trait(id, body, loc) \
+	gen_str1(AST_TRAIT_DEF, id, body, loc)
+
+#define trait_apply_id(x) return_s(x, AST_TRAIT_APPLY)
+#define gen_trait_apply(id, loc) \
+	gen_str(AST_TRAIT_DEF, id, loc)
+
+#define struct_id(x) return_s(x, AST_STRUCT_DEF)
+#define struct_params(x) return_a0(x, AST_STRUCT_DEF)
+#define struct_body(x) return_a1(x, AST_STRUCT_DEF)
+#define gen_struct(id, params, body, loc) \
+	gen_str2(AST_STRUCT_DEF, id, params, body, loc)
+
+#define import_file(x) return_s(x, AST_IMPORT)
+#define gen_import(file, loc) \
+	gen_str(AST_IMPORT, file, loc)
+
+#define struct_cont_id(x) return_s(x, AST_STRUCT_CONT)
+#define struct_cont_params(x) return_a0(x, AST_STRUCT_CONT)
+#define struct_cont_body(x) return_a1(x, AST_STRUCT_CONT)
+#define gen_struct_cont(id, params, body, loc) \
+	gen_str2(AST_STRUCT_CONT, id, params, body, loc)
+
 #define str_val(x) return_s(x, AST_CONST_STR)
 #define gen_const_str(s, loc) \
 	gen_ast(AST_CONST_STR, NULL, NULL, NULL, NULL, NULL, s, 0, 0., loc)
diff --git a/include/fwd/scope.h b/include/fwd/scope.h
index e49eb0a..ebe0261 100644
--- a/include/fwd/scope.h
+++ b/include/fwd/scope.h
@@ -52,6 +52,8 @@ struct scope {
 	struct scope *children;
 
 	struct visible symbols;
+	struct visible traits;
+	struct visible types;
 
 	enum scope_flags flags;
 };
@@ -106,80 +108,18 @@ int scope_add_scratch(struct scope *scope, struct ast *scratch);
  */
 void scope_add_scope(struct scope *parent, struct scope *child);
 
-/**
- * Add variable to scope.
- * Propagates public variables up the file scope chain as references.
- *
- * @param scope Scope to add variable to.
- * @param var Variable to add to scope.
- * @return \c 0 when succesful, non-zero otherwise.
- */
-int scope_add_var(struct scope *scope, struct ast *var);
-
-/**
- * Add type to scope.
- * Propagates public types up the file scope chain as references.
- *
- * @param scope Scope to add type to.
- * @param type Type to add to scope.
- * @return \c 0 when succesful, non-zero otherwise.
- */
-int scope_add_type(struct scope *scope, char *id, struct ast *type);
 
-/**
- * Add procedure to scope.
- * Propagates public procedures up the file scope chain as references.
- *
- * @param scope Scope to add procedure to.
- * @param proc Procedure to add to scope.
- * @return \c 0 when succesful, non-zero otherwise.
- */
-int scope_add_proc(struct scope *scope, struct ast *proc);
-
-/**
- * Find a variable with ID in \p scope.
- * @note Only looks in the current scope, so doesn't see anything outside
- * of it. See file_scope_find_var().
- *
- * @param scope Scope to look in.
- * @param id ID of variable to find.
- * @return Pointer to the AST node corresponding to \p id if found,
- * otherwise \c NULL.
- */
-struct ast *scope_find_var(struct scope *scope, char *id);
+int scope_add_symbol(struct scope *scope, struct ast *symbol);
 struct ast *scope_find_symbol(struct scope *scope, char *id);
-
-/**
- * Find a procedure with ID in \p scope.
- * @note Only looks in the current scope, so doesn't see anything outside
- * of it. See file_scope_find_proc().
- *
- * @param scope Scope to look in.
- * @param id ID of procedure to find.
- * @return Pointer to the AST node corresponding to \p id if found,
- * otherwise \c NULL.
- */
-struct ast *scope_find_proc(struct scope *scope, char *id);
-
-/**
- * Find a variable with ID visible to \p scope.
- *
- * @param scope Scope to look in.
- * @param id ID of variable to find.
- * @return Pointer to the AST node corresponding to \p id if found,
- * otherwise \c NULL.
- */
-struct ast *file_scope_find_var(struct scope *scope, char *id);
 struct ast *file_scope_find_symbol(struct scope *scope, char *id);
 
-/**
- * Find a procedure with ID visible to \p scope.
- *
- * @param scope Scope to look in.
- * @param id ID of procedure to find.
- * @return Pointer to the AST node corresponding to \p id if found,
- * otherwise \c NULL.
- */
-struct ast *file_scope_find_proc(struct scope *scope, char *id);
+int scope_add_type(struct scope *scope, struct ast *type);
+int scope_add_chain(struct scope *scope, struct ast *type);
+struct ast *scope_find_type(struct scope *scope, char *id);
+struct ast *file_scope_find_type(struct scope *scope, char *id);
+
+int scope_add_trait(struct scope *scope, struct ast *trait);
+struct ast *scope_find_trait(struct scope *scope, char *id);
+struct ast *file_scope_find_trait(struct scope *scope, char *id);
 
 #endif /* SCOPE_H */