diff options
Diffstat (limited to 'base.h')
| -rw-r--r-- | base.h | 39 |
1 files changed, 32 insertions, 7 deletions
@@ -81,28 +81,48 @@ void sym_table_init(sym_table_t *table); char *sym_table_find(sym_table_t *table, sv_t sv); void sym_table_cleanup(sym_table_t *table); -/// Pointer tagging scheme for lisps +/// Basic defintions for a Lisp #define NIL 0 + typedef struct Obj lisp_t; +typedef struct +{ + lisp_t *car, *cdr; +} cons_t; + +typedef struct +{ + // 2 levels of indirection... disgusting + void *data; +} lvec_t; + +/// Pointer tagging scheme for lisps + typedef enum Tag { - TAG_NIL = 0b00000000, + TAG_NIL = 0b00000000, // Start of atomic types TAG_INT = 0b00000001, // special so we can encode 63 bit integers TAG_SYM = 0b00000100, - NUM_TAGS = 3, + TAG_CONS = 0b00000010, // Start of container types + TAG_VEC = 0b00000110, + NUM_TAGS = 5, } tag_t; enum Shift { - SHIFT_INT = 1, - SHIFT_SYM = 8, + SHIFT_INT = 1, + SHIFT_SYM = 8, + SHIFT_CONS = 8, + SHIFT_VEC = 8, }; enum Mask { - MASK_INT = 0b00000001, - MASK_SYM = 0b11111111, + MASK_INT = 0b00000001, + MASK_SYM = 0b11111111, + MASK_CONS = 0b11111111, + MASK_VEC = 0b11111111, }; #define TAG(PTR, TYPE) ((lisp_t *)(((PTR) << SHIFT_##TYPE) | TAG_##TYPE)) @@ -114,7 +134,12 @@ enum Mask lisp_t *tag_int(i64 i); lisp_t *tag_sym(char *str); +lisp_t *tag_cons(cons_t *cons); +lisp_t *tag_vec(lvec_t *lvec); + i64 as_int(lisp_t *); char *as_sym(lisp_t *); +cons_t *as_cons(lisp_t *); +void *as_vec(lisp_t *); #endif |