altos/lisp: Allow macro/nlambda/lexpr to have multiple args

Entries from the params are bound to the formals with whatever
remaining formals there are bound to the last argument as a list.
This makes writing functions a bit easier.

Signed-off-by: Keith Packard <keithp@keithp.com>

diff --git a/src/lisp/ao_lisp_lambda.c b/src/lisp/ao_lisp_lambda.c
index 8b7617144b61d4625ab56d0719f46fcc2b92826b..186236f6eb7e8f3e5373050dbac8a76b48684b61 100644 (file)
--- a/src/lisp/ao_lisp_lambda.c
+++ b/src/lisp/ao_lisp_lambda.c
@@ -134,6 +134,8 @@ ao_lisp_lambda_eval(void)
        struct ao_lisp_frame    *next_frame;
        int                     args_wanted;
        int                     args_provided;
+       int                     f;
+       struct ao_lisp_cons     *vals
 
        DBGI("lambda "); DBG_POLY(ao_lisp_lambda_poly(lambda)); DBG("\n");
 
@@ -141,12 +143,14 @@ ao_lisp_lambda_eval(void)
 
        /* Create a frame to hold the variables
         */
-       if (lambda->args == AO_LISP_FUNC_LAMBDA)
-               args_provided = ao_lisp_cons_length(cons) - 1;
-       else
-               args_provided = 1;
-       if (args_wanted != args_provided)
-               return ao_lisp_error(AO_LISP_INVALID, "need %d args, not %d", args_wanted, args_provided);
+       args_provided = ao_lisp_cons_length(cons) - 1;
+       if (lambda->args == AO_LISP_FUNC_LAMBDA) {
+               if (args_wanted != args_provided)
+                       return ao_lisp_error(AO_LISP_INVALID, "need %d args, got %d", args_wanted, args_provided);
+       } else {
+               if (args_provided < args_wanted - 1)
+                       return ao_lisp_error(AO_LISP_INVALID, "need at least %d args, got %d", args_wanted, args_provided);
+       }
 
        next_frame = ao_lisp_frame_new(args_wanted);
 
@@ -155,12 +159,10 @@ ao_lisp_lambda_eval(void)
        cons = ao_lisp_poly_cons(ao_lisp_stack->values);
        code = ao_lisp_poly_cons(lambda->code);
        args = ao_lisp_poly_cons(ao_lisp_arg(code, 0));
+       vals = ao_lisp_poly_cons(cons->cdr);
 
        switch (lambda->args) {
-       case AO_LISP_FUNC_LAMBDA: {
-               int                     f;
-               struct ao_lisp_cons     *vals = ao_lisp_poly_cons(cons->cdr);
-
+       case AO_LISP_FUNC_LAMBDA:
                for (f = 0; f < args_wanted; f++) {
                        DBGI("bind "); DBG_POLY(args->car); DBG(" = "); DBG_POLY(vals->car); DBG("\n");
                        next_frame->vals[f].atom = args->car;
@@ -170,13 +172,19 @@ ao_lisp_lambda_eval(void)
                }
                ao_lisp_cons_free(cons);
                break;
-       }
        case AO_LISP_FUNC_LEXPR:
        case AO_LISP_FUNC_NLAMBDA:
        case AO_LISP_FUNC_MACRO:
-               DBGI("bind "); DBG_POLY(args->car); DBG(" = "); DBG_POLY(cons->cdr); DBG("\n");
-               next_frame->vals[0].atom = args->car;
-               next_frame->vals[0].val = cons->cdr;
+               for (f = 0; f < args_wanted - 1; f++) {
+                       DBGI("bind "); DBG_POLY(args->car); DBG(" = "); DBG_POLY(vals->car); DBG("\n");
+                       next_frame->vals[f].atom = args->car;
+                       next_frame->vals[f].val = vals->car;
+                       args = ao_lisp_poly_cons(args->cdr);
+                       vals = ao_lisp_poly_cons(vals->cdr);
+               }
+               DBGI("bind "); DBG_POLY(args->car); DBG(" = "); DBG_POLY(); DBG("\n");
+               next_frame->vals[f].atom = args->car;
+               next_frame->vals[f].val = ao_lisp_cons_poly(vals);
                break;
        }
        next_frame->prev = lambda->frame;