X-Git-Url: https://git.gag.com/?a=blobdiff_plain;f=src%2Flisp%2Fao_lisp_eval.c;h=c5addcb0abd1baae60afe6ea76a51dd9e8da6420;hb=fd7df330470c7c2f12ca3ce28d920c3b278108d5;hp=f3372f2a4e52ee73c39985ec9cd3584268694d4c;hpb=a3535e28a74055c3b303dbb4111cb3d38c2817e2;p=fw%2Faltos diff --git a/src/lisp/ao_lisp_eval.c b/src/lisp/ao_lisp_eval.c index f3372f2a..c5addcb0 100644 --- a/src/lisp/ao_lisp_eval.c +++ b/src/lisp/ao_lisp_eval.c @@ -12,7 +12,7 @@ * General Public License for more details. */ -#define DBG_EVAL 0 +#define DBG_EVAL 1 #include "ao_lisp.h" #include @@ -478,6 +478,85 @@ ao_lisp_eval_cond_test(void) return 1; } +/* + * Evaluate a list of sexprs, returning the value from the last one. + * + * ao_lisp_progn records the list in stack->sexprs, so we just need to + * walk that list. Set ao_lisp_v to the car of the list and jump to + * eval_sexpr. When that's done, it will land in eval_val. For all but + * the last, leave a stack frame with eval_progn set so that we come + * back here. For the last, don't add a stack frame so that we can + * just continue on. + */ +static int +ao_lisp_eval_progn(void) +{ + DBGI("progn: "); DBG_POLY(ao_lisp_v); DBG(" sexprs "); DBG_POLY(ao_lisp_stack->sexprs); DBG("\n"); + DBGI(".. frame "); DBG_POLY(ao_lisp_frame_poly(ao_lisp_frame_current)); DBG("\n"); + DBGI(".. saved frame "); DBG_POLY(ao_lisp_stack->frame); DBG("\n"); + + if (!ao_lisp_stack->sexprs) { + ao_lisp_v = AO_LISP_NIL; + ao_lisp_stack->state = eval_val; + } else { + ao_lisp_v = ao_lisp_poly_cons(ao_lisp_stack->sexprs)->car; + ao_lisp_stack->sexprs = ao_lisp_poly_cons(ao_lisp_stack->sexprs)->cdr; + if (ao_lisp_stack->sexprs) { + ao_lisp_stack->state = eval_progn; + if (!ao_lisp_stack_push()) + return 0; + } + ao_lisp_stack->state = eval_sexpr; + } + return 1; +} + +/* + * Conditionally execute a list of sexprs while the first is true + */ +static int +ao_lisp_eval_while(void) +{ + DBGI("while: "); DBG_POLY(ao_lisp_stack->sexprs); DBG("\n"); + DBGI(".. frame "); DBG_POLY(ao_lisp_frame_poly(ao_lisp_frame_current)); DBG("\n"); + DBGI(".. saved frame "); DBG_POLY(ao_lisp_stack->frame); DBG("\n"); + + if (!ao_lisp_stack->sexprs) { + ao_lisp_v = AO_LISP_NIL; + ao_lisp_stack->state = eval_val; + } else { + ao_lisp_v = ao_lisp_poly_cons(ao_lisp_stack->sexprs)->car; + ao_lisp_stack->state = eval_while_test; + if (!ao_lisp_stack_push()) + return 0; + ao_lisp_stack->state = eval_sexpr; + } + return 1; +} + +/* + * Check the while condition, terminate the loop if nil. Otherwise keep going + */ +static int +ao_lisp_eval_while_test(void) +{ + DBGI("while_test: "); DBG_POLY(ao_lisp_v); DBG(" sexprs "); DBG_POLY(ao_lisp_stack->sexprs); DBG("\n"); + DBGI(".. frame "); DBG_POLY(ao_lisp_frame_poly(ao_lisp_frame_current)); DBG("\n"); + DBGI(".. saved frame "); DBG_POLY(ao_lisp_stack->frame); DBG("\n"); + + if (ao_lisp_v) { + ao_lisp_v = ao_lisp_poly_cons(ao_lisp_stack->sexprs)->cdr; + if (ao_lisp_v) + ao_lisp_v = ao_lisp_poly_cons(ao_lisp_v)->car; + ao_lisp_stack->state = eval_while; + if (!ao_lisp_stack_push()) + return 0; + } + else + ao_lisp_stack->state = eval_val; + return 1; +} + static int (*const evals[])(void) = { [eval_sexpr] = ao_lisp_eval_sexpr, [eval_val] = ao_lisp_eval_val, @@ -485,6 +564,9 @@ static int (*const evals[])(void) = { [eval_exec] = ao_lisp_eval_exec, [eval_cond] = ao_lisp_eval_cond, [eval_cond_test] = ao_lisp_eval_cond_test, + [eval_progn] = ao_lisp_eval_progn, + [eval_while] = ao_lisp_eval_while, + [eval_while_test] = ao_lisp_eval_while_test, }; ao_poly