TODO(#395)

[nothing.git] / src / script / expr.h

diff --git a/src/script/expr.h b/src/script/expr.h
index bd57c657c9c570d0084dc7e6f3f9e5c77618456c..3f24c72b6fa02123c1252e7aaef315665fae1291 100644 (file)
--- a/src/script/expr.h
+++ b/src/script/expr.h
@@ -1,21 +1,25 @@
-#ifndef ATOM_H_
-#define ATOM_H_
+#ifndef EXPR_H_
+#define EXPR_H_
 
 #include <stdlib.h>
 #include <stdbool.h>
 
 typedef struct Gc Gc;
+typedef struct Scope Scope;
 
 struct Cons;
 struct Atom;
 
-// TODO(#321): get rid of gc argument from expr macros (just assume that it's `gc` in the current scope)
 #define NUMBER(G, X) atom_as_expr(create_number_atom(G, X))
 #define STRING(G, S) atom_as_expr(create_string_atom(G, S, NULL))
 #define SYMBOL(G, S) atom_as_expr(create_symbol_atom(G, S, NULL))
+#define NATIVE(G, F, P) atom_as_expr(create_native_atom(G, F, P))
 #define CONS(G, CAR, CDR) cons_as_expr(create_cons(G, CAR, CDR))
 #define NIL(G) SYMBOL(G, "nil")
 
+#define CAR(O) ((O).cons->car)
+#define CDR(O) ((O).cons->cdr)
+
 enum ExprType
 {
     EXPR_ATOM = 0,
@@ -23,7 +27,6 @@ enum ExprType
     EXPR_VOID
 };
 
-// TODO(#285): there is no way to execute struct Expr
 struct Expr
 {
     enum ExprType type;
@@ -39,12 +42,30 @@ struct Expr void_expr(void);
 
 void destroy_expr(struct Expr expr);
 void print_expr_as_sexpr(struct Expr expr);
+int expr_as_sexpr(struct Expr expr, char *output, size_t n);
+
+// TODO(#337): EvalResult does not belong to expr unit
+struct EvalResult
+{
+    bool is_error;
+    struct Expr expr;
+};
+
+
+typedef struct EvalResult (*NativeFunction)(void *param, Gc *gc, struct Scope *scope, struct Expr args);
+
+struct Native
+{
+    NativeFunction fun;
+    void *param;
+};
 
 enum AtomType
 {
     ATOM_SYMBOL = 0,
     ATOM_NUMBER,
     ATOM_STRING,
+    ATOM_NATIVE
 };
 
 struct Atom
@@ -52,15 +73,18 @@ struct Atom
     enum AtomType type;
     union
     {
-        float num;             // ATOM_NUMBER
-        char *sym;             // ATOM_SYMBOL
-        char *str;             // ATOM_STRING
+        // TODO(#330): Atom doesn't support floats
+        long int num;           // ATOM_NUMBER
+        char *sym;              // ATOM_SYMBOL
+        char *str;              // ATOM_STRING
+        struct Native native;   // ATOM_NATIVE
     };
 };
 
-struct Atom *create_number_atom(Gc *gc, float num);
+struct Atom *create_number_atom(Gc *gc, long int num);
 struct Atom *create_string_atom(Gc *gc, const char *str, const char *str_end);
 struct Atom *create_symbol_atom(Gc *gc, const char *sym, const char *sym_end);
+struct Atom *create_native_atom(Gc *gc, NativeFunction fun, void *param);
 void destroy_atom(struct Atom *atom);
 void print_atom_as_sexpr(struct Atom *atom);
 
@@ -74,4 +98,4 @@ struct Cons *create_cons(Gc *gc, struct Expr car, struct Expr cdr);
 void destroy_cons(struct Cons *cons);
 void print_cons_as_sexpr(struct Cons *cons);
 
-#endif  // ATOM_H_
+#endif  // EXPR_H_