diff options
| author | Keith Packard <keithp@keithp.com> | 2016-11-15 09:55:22 -0800 |
|---|---|---|
| committer | Keith Packard <keithp@keithp.com> | 2017-02-20 11:16:51 -0800 |
| commit | 974717eb9dad105c9897ee24f953d98d57eaec77 (patch) | |
| tree | ea77eec1b39f859353f17ad384950f6bd982c569 /src/lisp/ao_lisp_eval.c | |
| parent | b3b5bd2c14cfcde6c551a87ee6da08a53f1e4bc6 (diff) | |
altos/lisp: Evaluate macros once, then smash them into place
This assumes that macros are all pure functions, which should be true
for syntactic macros.
Signed-off-by: Keith Packard <keithp@keithp.com>
Diffstat (limited to 'src/lisp/ao_lisp_eval.c')
| -rw-r--r-- | src/lisp/ao_lisp_eval.c | 23 |
1 files changed, 21 insertions, 2 deletions
diff --git a/src/lisp/ao_lisp_eval.c b/src/lisp/ao_lisp_eval.c index 5cc1b75a..3af56796 100644 --- a/src/lisp/ao_lisp_eval.c +++ b/src/lisp/ao_lisp_eval.c @@ -298,7 +298,7 @@ ao_lisp_eval_formal(void) break; case AO_LISP_FUNC_MACRO: /* Evaluate the result once more */ - ao_lisp_stack->state = eval_sexpr; + ao_lisp_stack->state = eval_macro; if (!ao_lisp_stack_push()) return 0; @@ -308,7 +308,6 @@ ao_lisp_eval_formal(void) prev = ao_lisp_poly_stack(ao_lisp_stack->prev); ao_lisp_stack->state = eval_sexpr; ao_lisp_stack->sexprs = prev->sexprs; - prev->sexprs = AO_LISP_NIL; DBGI(".. start macro\n"); DBGI(".. sexprs "); DBG_POLY(ao_lisp_stack->sexprs); DBG("\n"); @@ -555,6 +554,25 @@ ao_lisp_eval_while_test(void) return 1; } +/* + * Replace the original sexpr with the macro expansion, then + * execute that + */ +static int +ao_lisp_eval_macro(void) +{ + DBGI("macro: "); DBG_POLY(ao_lisp_v); DBG(" sexprs "); DBG_POLY(ao_lisp_stack->sexprs); DBG("\n"); + + if (ao_lisp_poly_type(ao_lisp_v) == AO_LISP_CONS) { + *ao_lisp_poly_cons(ao_lisp_stack->sexprs) = *ao_lisp_poly_cons(ao_lisp_v); + ao_lisp_v = ao_lisp_stack->sexprs; + DBGI("sexprs rewritten to: "); DBG_POLY(ao_lisp_v); DBG("\n"); + } + ao_lisp_stack->sexprs = AO_LISP_NIL; + ao_lisp_stack->state = eval_sexpr; + return 1; +} + static int (*const evals[])(void) = { [eval_sexpr] = ao_lisp_eval_sexpr, [eval_val] = ao_lisp_eval_val, @@ -565,6 +583,7 @@ static int (*const evals[])(void) = { [eval_progn] = ao_lisp_eval_progn, [eval_while] = ao_lisp_eval_while, [eval_while_test] = ao_lisp_eval_while_test, + [eval_macro] = ao_lisp_eval_macro, }; /* |