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Monorepo for Aesthetic.Computer aesthetic.computer
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123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129/* lisp850-opt.c with BCD boxing (optimized version) by Robert A. van Engelen 2022 */#define I unsigned#define L double#define T *(char*)&#define A (char*)cell#define N 1024I hp=0,sp=N,ATOM=32,PRIM=48,CONS=64,CLOS=80,NIL=96;L cell[N],nil,tru,err,env;L box(I t,I i) { L x = i+10; T x = t; return x; }I ord(L x) { T x &= 15; return (I)x-10; }L num(L n) { T n &= 159; return n; }L atom(const char *s) { I i = 0; while (i < hp && strcmp(A+i,s)) i += strlen(A+i)+1; if (i == hp && (hp += strlen(strcpy(A+i,s))+1) > sp<<3) abort(); return box(ATOM,i);}L cons(L x,L y) { cell[--sp] = x; cell[--sp] = y; if (hp > sp<<3) abort(); return box(CONS,sp); }L car(L p) { return (T p&224) == CONS ? cell[T p &= 15,(I)p-9] : err; }L cdr(L p) { return (T p&224) == CONS ? cell[T p &= 15,(I)p-10] : err; }L pair(L v,L x,L e) { return cons(cons(v,x),e); }L closure(L v,L x,L e) { return box(CLOS,ord(pair(v,x,e == env ? nil : e))); }L assoc(L v,L e) { while (T e == CONS && v != car(car(e))) e = cdr(e); return T e == CONS ? cdr(car(e)) : err; }I not(L x) { return T x == NIL; }I let(L x) { return !not(x) && !not(cdr(x)); }L eval(L,L),parse();L evlis(L t,L e) { L s,*p; for (s = nil,p = &s; T t == CONS; p = cell+sp,t = cdr(t)) *p = cons(eval(car(t),e),nil); if (T t == ATOM) *p = assoc(t,e); return s;}L f_eval(L t,L *e) { return car(evlis(t,*e)); }L f_quote(L t,L *_) { return car(t); }L f_cons(L t,L *e) { return t = evlis(t,*e),cons(car(t),car(cdr(t))); }L f_car(L t,L *e) { return car(car(evlis(t,*e))); }L f_cdr(L t,L *e) { return cdr(car(evlis(t,*e))); }L f_add(L t,L *e) { L n = car(t = evlis(t,*e)); while (!not(t = cdr(t))) n += car(t); return num(n); }L f_sub(L t,L *e) { L n = car(t = evlis(t,*e)); while (!not(t = cdr(t))) n -= car(t); return num(n); }L f_mul(L t,L *e) { L n = car(t = evlis(t,*e)); while (!not(t = cdr(t))) n *= car(t); return num(n); }L f_div(L t,L *e) { L n = car(t = evlis(t,*e)); while (!not(t = cdr(t))) n /= car(t); return num(n); }L f_int(L t,L *e) { L n = car(evlis(t,*e)); return n-1e9 < 0 && n+1e9 > 0 ? (long)n : n; }L f_lt(L t,L *e) { return t = evlis(t,*e),car(t) - car(cdr(t)) < 0 ? tru : nil; }L f_eq(L t,L *e) { return t = evlis(t,*e),car(t) == car(cdr(t)) ? tru : nil; }L f_pair(L t,L *e) { L x = car(evlis(t,*e)); return T x == CONS ? tru : nil; }L f_or(L t,L *e) { L x = nil; while (T t != NIL && not(x = eval(car(t),*e))) t = cdr(t); return x; }L f_and(L t,L *e) { L x = tru; while (T t != NIL && !not(x = eval(car(t),*e))) t = cdr(t); return x; }L f_not(L t,L *e) { return not(car(evlis(t,*e))) ? tru : nil; }L f_cond(L t,L *e) { while (T t != NIL && not(eval(car(car(t)),*e))) t = cdr(t); return car(cdr(car(t))); }L f_if(L t,L *e) { return car(cdr(not(eval(car(t),*e)) ? cdr(t) : t)); }L f_leta(L t,L *e) { for (;let(t); t = cdr(t)) *e = pair(car(car(t)),eval(car(cdr(car(t))),*e),*e); return car(t); }L f_lambda(L t,L *e) { return closure(car(t),car(cdr(t)),*e); }L f_define(L t,L *e) { env = pair(car(t),eval(car(cdr(t)),*e),env); return car(t); }struct { const char *s; L (*f)(L,L*); short t; } prim[] = {{"eval", f_eval, 1},{"quote", f_quote, 0},{"cons", f_cons,0},{"car", f_car, 0},{"cdr",f_cdr,0},{"+", f_add, 0},{"-", f_sub, 0},{"*", f_mul, 0},{"/", f_div, 0},{"int", f_int, 0},{"<", f_lt, 0},{"eq?", f_eq, 0},{"or", f_or, 0},{"and", f_and, 0},{"not", f_not, 0},{"cond",f_cond,1},{"if", f_if, 1},{"let*",f_leta,1},{"lambda",f_lambda,0},{"define",f_define,0},{"pair?",f_pair,0},{0}};L eval(L x,L e) { L f,v,d; while (1) { if (T x == ATOM) return assoc(x,e); if (T x != CONS) return x; f = eval(car(x),e); x = cdr(x); if (T f == PRIM) { x = prim[ord(f)].f(x,&e); if (prim[ord(f)].t) continue; return x; } if (T f != CLOS) return err; v = car(car(f)); d = cdr(f); if (T d == NIL) d = env; for (;T v == CONS && T x == CONS; v = cdr(v),x = cdr(x)) d = pair(car(v),eval(car(x),e),d); for (x = T x == CONS ? evlis(x,e) : eval(x,e); T v == CONS; v = cdr(v),x = cdr(x)) d = pair(car(v),car(x),d); if (T v == ATOM) d = pair(v,x,d); x = cdr(car(f)); e = d; }}char buf[40],see = ' ';void look() { int c = getchar(); see = c; if (c == -1) exit(0); }I seeing(char c) { return c == ' ' ? see > 0 && see <= c : see == c; }char get() { char c = see; look(); return c; }char scan() { int i = 0; while (seeing(' ')) look(); if (seeing('(') || seeing(')') || seeing('\'')) buf[i++] = get(); else do buf[i++] = get(); while (i < 39 && !seeing('(') && !seeing(')') && !seeing(' ')); return buf[i] = 0,*buf;}L read() { return scan(),parse(); }L list() { L t,*p; for (t = nil,p = &t; ; *p = cons(parse(),nil),p = cell+sp) { if (scan() == ')') return t; if (*buf == '.' && !buf[1]) return *p = read(),scan(),t; }}L parse() { L n; int i; if (*buf == '(') return list(); if (*buf == '\'') return cons(atom("quote"),cons(read(),nil)); i = strlen(buf); return isdigit(buf[*buf == '-']) && sscanf(buf,"%lg%n",&n,&i) > 0 && !buf[i] ? n : atom(buf);}void print(L);void printlist(L t) { for (putchar('('); ; putchar(' ')) { print(car(t)); if (not(t = cdr(t))) break; if (T t != CONS) { printf(" . "); print(t); break; } } putchar(')');}void print(L x) { if (T x == NIL) printf("()"); else if (T x == ATOM) printf("%s",A+ord(x)); else if (T x == PRIM) printf("<%s>",prim[ord(x)].s); else if (T x == CONS) printlist(x); else if (T x == CLOS) printf("{%u}",ord(x)); else printf("%.10lg",x);}void gc() { sp = ord(env); }int main() { int i; printf("lisp850"); nil = box(NIL,0); err = atom("ERR"); tru = atom("#t"); env = pair(tru,tru,nil); for (i = 0; prim[i].s; ++i) env = pair(atom(prim[i].s),box(PRIM,i),env); while (1) { printf("\n%u>",sp-hp/8); print(eval(read(),env)); gc(); }}