Esempio n. 1
0
int main(int argc, char* *argv){
    init_parser();
    lenv *e = lenv_new();
    lenv_add_builtins(e);
    if (access(STD_LIB, F_OK) != -1){
        lval *err = builtin_load(e, lval_add(lval_sexpr(), lval_str((char *)STD_LIB)));
        if (err->type == LVAL_ERR) lval_println(err);
        lval_del(err);
    } else {
        printf("Can't find stdlib at %s.\n", STD_LIB);
    }

    if (argc > 1){
        for (int i = 1; i < argc; i++){
            lval *args = lval_add(lval_sexpr(), lval_str(argv[i]));
            lval *x = builtin_load(e, args);

            if (x->type == LVAL_ERR) lval_println(x);
            lval_del(x);
        }
    } else {
        puts("Aroma Version v0.0.0.1");
        puts("Press Ctrl+C to Exit.");

        char *input = NULL;
        mpc_result_t r;

        while (true){
            input = readline(">>> ");
            if (strlen(input) < 1) {
                continue;
            }
            add_history(input);
            if (mpc_parse("<stdin>", input, Lispy, &r)){
                /* mpc_ast_print(r.output); */
                lval *x = lval_eval(e, lval_read(r.output));
                lval_println(x);
                lval_del(x);

                mpc_ast_delete(r.output);
            } else {
                mpc_err_print(r.error);
                mpc_err_delete(r.error);
            }
            /* printf("%s\n", input); */
            free(input);
        }
    }

    lenv_del(e);
    cleanup_parser();

    return 0;
}
Esempio n. 2
0
int main(int argc, char** argv){
    puts("yafl Version 0.0.1");
    puts("Press CTRL+C to Exit\n");

    gen_parsers();
    lenv* e = lenv_new();
    lenv_add_builtins(e);
    lval* core = lval_add(lval_sexpr(), lval_str("src/yfl/core.yfl"));
    //printf("gets here");
    lval* core_loaded = builtin_load(e, core);

    if(core_loaded->type == LVAL_ERR) {lval_println(core_loaded);}
    lval_del(core_loaded);

    if(argc >= 2){ //execute file
        for(int i = 1; i < argc; i++){

            lval* args = lval_add(lval_sexpr(), lval_str(argv[i]));

            lval* x = builtin_load(e, args);

            if(x->type == LVAL_ERR) { lval_println(x); }
            lval_del(x);
        }
    }
    else{ //Start REPL

        while(1){
            char* input = readline("yafl> ");
            add_history(input);
            mpc_result_t r;
            if(mpc_parse("<stdin>", input, Yafl, &r)){

                lval* x = lval_eval(e, lval_read(r.output));
                lval_println(x);
                lval_del(x);
                mpc_ast_delete(r.output);
            }else{
                mpc_err_print(r.error);
                mpc_err_delete(r.error);
            }

            free(input);
        }
    }

    teardown_parsers();
    return 0;
}
Esempio n. 3
0
lval *builtin_var(lenv *e, lval *a, char *func)
{
  LASSERT_TYPE("def", a, 0, LVAL_QEXPR);
  lval *syms = a->cell[0];
  for (int i = 0; i < syms->count; i++)
  {
    LASSERT(a, (syms->cell[i]->type == LVAL_SYM),
      "Function 'def' cannot define non-symbol"
      "\n  got %s expected %s",
      ltype_name(syms->cell[i]->type), ltype_name(LVAL_SYM));
  }
  LASSERT(a, (syms->count == a->count-1),
    "Function 'def' passed too many arguments for symbols"
    "\n  got %i expected %i",
    syms->count, a->count-1);
  for (int i = 0; i < syms->count; i++)
  {
    if (strcmp(func, "def") == 0)
    {
      lenv_def(e, syms->cell[i], a->cell[i + 1]);
    }
    if (strcmp(func, "=") == 0)
    {
      lenv_put(e, syms->cell[i], a->cell[i + 1]);
    }
  }
  lval_del(a);
  return lval_sexpr();
}
Esempio n. 4
0
lval * ast_load_eval(char* fn, lenv *env) {
    lval *r;
    mpc_result_t parsed;
    lval *ast;
    lval *result;

    if (mpc_parse_contents(fn, Lispy, &parsed)) {
        ast = ast_read(parsed.output);
        mpc_ast_delete(parsed.output);
        while (ast->expr->count) {
            result = lval_eval(expr_pop(ast->expr, 0), env);
            if (result->type == LVAL_ERR) lval_println(result);
            lval_del(result);
        }
        lval_del(ast);
        r = lval_sexpr();
    }
    else {
        char *err = mpc_err_string(parsed.error);
        mpc_err_delete(parsed.error);
        r = lval_err(err);
        free(err);
    }

    return r;
}
Esempio n. 5
0
lval* lval_call(lenv* e, lval* f, lval* a){

    if(f->builtin) {
        return f->builtin(e,a);
    }

    int given = a->count;
    int total = f->formals->count;


    while(a->count){
        if(f->formals->count == 0){
            lval_del(a); return lval_err("too many args. expected %i, got %i",
                                         total, given);
        }

        lval* sym = lval_pop(f->formals, 0);

        if(strcmp(sym->sym, "&") == 0){
            if(f->formals->count != 1){
                lval_del(a);
                return lval_err("too many args after '&'.  only 1 allowed");
            }

            lval* nsym = lval_pop(f->formals, 0);
            lenv_put(f->env, nsym, builtin_list(e, a));
            lval_del(sym); lval_del(nsym);
            break;
        }

        lval* val = lval_pop(a, 0);
        lenv_put(f->env, sym, val);
        lval_del(sym);
        lval_del(val);
    }

    lval_del(a);

    if(f->formals->count >0 &&
       strcmp(f->formals->cell[0]->sym, "&") == 0){
        if(f->formals->count != 2){
            return lval_err("'&' should be followed by a single arg");
        }

        lval_del(lval_pop(f->formals, 0));

        lval* sym = lval_pop(f->formals, 0);
        lval* val = lval_qexpr();

        lenv_put(f->env, sym, val);
        lval_del(sym); lval_del(val);
    }

    if(f->formals->count == 0){
        f->env->par = e;
        return builtin_eval(f->env, lval_add(lval_sexpr(), lval_copy(f->body)));
    }else{
        return lval_copy(f);
    }
}
Esempio n. 6
0
lval* builtin_var(lenv* e, lval* a, char* func)
{
  LASSERT_TYPE(func, a, 0, LVAL_QEXPR);

  lval* syms = a->cell[0];

  for (int i = 0; i < syms->count; i++)
    LASSERT(a, syms->cell[i]->type == LVAL_SYM,
      "Function '%s' cannot define a non-symbol.  Got %s, Expected %s.",
      func, ltype_name(syms->cell[i]->type), ltype_name(LVAL_SYM));

  LASSERT(a, syms->count == a->count - 1,
    "Function '%s' passed too many arguments for symbols.  Got %i, Expected %i.",
    func, syms->count, a->count - 1);

  for (int i = 0; i < syms->count; i++)
  {
    if (strcmp(func, "def") == 0)
      lenv_def(e, syms->cell[i], a->cell[i+1]);
    
    if (strcmp(func, "=") == 0)
      lenv_put(e, syms->cell[i], a->cell[i+1]);
  }

  lval_del(a);
  return lval_sexpr();
}
Esempio n. 7
0
lval *lval_read(mpc_ast_t *t) {
    if (strstr(t->tag, "long")) {
        return lval_read_long(t);
    }
    if (strstr(t->tag, "double")) {
        return lval_read_double(t);
    }
    if (strstr(t->tag, "symbol")) {
        return lval_sym(t->contents);
    }

    lval *x = NULL;
    if (strcmp(t->tag, ">") == 0) {
        x = lval_sexpr();
    }
    if (strstr(t->tag, "sexpr")) {
        x = lval_sexpr();
    }
    if (strstr(t->tag, "qexpr")) {
        x = lval_qexpr();
    }

    for (int i = 0; i < t->children_num; i++) {
        mpc_ast_t *child = t->children[i];
        char *contents = child->contents;
        if (strcmp(contents, "(") == 0) {
            continue;
        }
        if (strcmp(contents, ")") == 0) {
            continue;
        }
        if (strcmp(contents, "{") == 0) {
            continue;
        }
        if (strcmp(contents, "}") == 0) {
            continue;
        }

        if (strcmp(child->tag, "regex") == 0) {
            continue;
        }

        x = lval_add(x, lval_read(child));
    }

    return x;
}
Esempio n. 8
0
lval * ast_read(mpc_ast_t *t) {
    int i;
    lval *x;

    if (strstr(t->tag, "number")) return ast_read_num(t);

    if (strstr(t->tag, "symbol")) {
        if (!strcmp(t->contents, "true")) {
            return lval_boolean(1);
        }
        else if (!strcmp(t->contents, "false")) {
            return lval_boolean(0);
        }
        else {
            return lval_sym(t->contents);
        }
    }

    if (strstr(t->tag, "string")) {
        ssize_t sz = strlen(t->contents) + 1 - 2 /* quotes */;
        char *unescaped = malloc(sz);
        memcpy(unescaped, t->contents+1, sz);
        unescaped[sz-1] = '\0';
        unescaped = mpcf_unescape(unescaped);
        x = lval_str(unescaped);
        free(unescaped);
        return x;
    }

    if (strstr(t->tag, "comment")) return NULL;

    if (strstr(t->tag, "qexpr")) {
        x = lval_qexpr();
    }
    else {
        assert(
            (strcmp(t->tag, ">") == 0) ||
            strstr(t->tag, "sexpr")
        );
        x = lval_sexpr();
    }

    for (i = 0; i < t->children_num; ++i) {
        lval *v;
        if (
            (strlen(t->children[i]->contents) == 1) &&
            strstr("(){}", t->children[i]->contents)
        ) continue;
        if (!strcmp(t->children[i]->tag, "regex")) continue;
        v = ast_read(t->children[i]);
        if(v) lval_append(x, v);
    }

    return x;
}
Esempio n. 9
0
File: lval.c Progetto: tsmarsh/lispy
lval* lval_read(mpc_ast_t* t) {
  if (strstr(t->tag, "number")) { return lval_read_num(t); }
  if (strstr(t->tag, "symbol")) { return lval_sym(t->contents); }

  lval* x = NULL;
  if (strcmp(t->tag, ">") == 0) { x = lval_sexpr(); } 
  if (strstr(t->tag, "sexpr"))  { x = lval_sexpr(); }
  if (strstr(t->tag, "qexpr"))  { x = lval_qexpr(); }

  for (int i = 0; i < t->children_num; i++) {
    if (strcmp(t->children[i]->contents, "(") == 0) { continue; }
    if (strcmp(t->children[i]->contents, ")") == 0) { continue; }
    if (strcmp(t->children[i]->contents, "}") == 0) { continue; }
    if (strcmp(t->children[i]->contents, "{") == 0) { continue; }
    if (strcmp(t->children[i]->tag,  "regex") == 0) { continue; }
    x = lval_add(x, lval_read(t->children[i]));
  }

  return x;
}
Esempio n. 10
0
lval* builtin_print(lenv* e, lval* a) {
  //Print each argument followed by a space
  for (int i = 0; i < a->count; i++) {
    lval_print(a->cell[i]); putchar(' ');
  }

  //Print a newline and delete args
  putchar('\n');
  lval_del(a);

  return lval_sexpr();
}
Esempio n. 11
0
lval* lval_read(mpc_ast_t* t) {

  /* If Symbol or Number return conversion to that type */
  if (strstr(t->tag, "number")) { return lval_read_num(t); }
  if (strstr(t->tag, "symbol")) { return lval_sym(t->contents); }

  /* If root (>) or sexpr then create empty list */
  lval* x = NULL;
  if (strcmp(t->tag, ">") == 0) { x = lval_sexpr(); }
  if (strstr(t->tag, "sexpr"))  { x = lval_sexpr(); }

  /* Fill this list with any valid expression contained within */
  for (int i = 0; i < t->children_num; i++) {
    if (strcmp(t->children[i]->contents, "(") == 0) { continue; }
    if (strcmp(t->children[i]->contents, ")") == 0) { continue; }
    if (strcmp(t->children[i]->contents, "}") == 0) { continue; }
    if (strcmp(t->children[i]->contents, "{") == 0) { continue; }
    if (strcmp(t->children[i]->tag,  "regex") == 0) { continue; }
    x = lval_add(x, lval_read(t->children[i]));
  }

  return x;
}
Esempio n. 12
0
lval *lval_read(mpc_ast_t *t)
{
  // convert symbols and nums to lvals
  if (strstr(t->tag, "number")) { return lval_read_num(t); }
  if (strstr(t->tag, "symbol")) { return lval_sym(t->contents); }

  // if root or sexpr creat empty list
  lval *x = NULL;
  if (strcmp(t->tag, ">") == 0) { x = lval_sexpr(); }
  if (strstr(t->tag, "sexpr"))  { x = lval_sexpr(); }
  if (strstr(t->tag, "qexpr"))  { x = lval_qexpr(); }

  // fill list with any valid expr contained within
  for (int i = 0; i < t->children_num; i++)
  {
    if (strcmp(t->children[i]->contents, "(") == 0) { continue; }
    if (strcmp(t->children[i]->contents, ")") == 0) { continue; }
    if (strcmp(t->children[i]->contents, "{") == 0) { continue; }
    if (strcmp(t->children[i]->contents, "}") == 0) { continue; }
    if (strcmp(t->children[i]->tag,  "regex") == 0) { continue; }
    x = lval_add(x, lval_read(t->children[i]));
  }
  return x;
}
Esempio n. 13
0
File: main.c Progetto: BillBai/Bisp
lval* lval_read(mpc_ast_t* t)
{
    if (strstr(t->tag, "number")) { return lval_read_num(t); }
    if (strstr(t->tag, "symbol")) { return lval_symbol(t->contents); }
    if (strstr(t->tag, "string")) { return lval_read_str(t); }

    // if root (>) or sexpr, cearte an empty lval_sexpr.
    lval *x = NULL;
    if (strcmp(t->tag, ">") == 0) { x = lval_sexpr(); }
    if (strstr(t->tag, "sexpr")) { x = lval_sexpr(); }
    if (strstr(t->tag, "qexpr")) { x = lval_qexpr(); }

    for (int i = 0; i < t->children_num; i++) {
        if (strcmp(t->children[i]->contents, "(") == 0) { continue; }
        if (strcmp(t->children[i]->contents, ")") == 0) { continue; }
        if (strcmp(t->children[i]->contents, "{") == 0) { continue; }
        if (strcmp(t->children[i]->contents, "}") == 0) { continue; }
        if (strcmp(t->children[i]->tag, "regex") == 0) { continue; }
        if (strstr(t->children[i]->tag, "comment")) { continue; }
        x = lval_add(x, lval_read(t->children[i]));
    }

    return x;
}
Esempio n. 14
0
int main(int argc, char** argv) {

    init_parser();

    /* initialize environment */
    lenv* e = lenv_new();
    lenv_add_builtins(e);

    /* load standard library functions */
    lval* x = builtin_load(e, lval_add(lval_sexpr(), lval_str("prelude.lsp")));
    if (x->type == LVAL_ERR) { lval_println(x); }
    lval_del(x);

    if (argc >= 2) {

        /* read from command line */
        parse_args(e, argc, argv);

    } else {

        /* interactive prompt */
        say_hello();
        while (1) {
            char* input = prompt();
            lval* x = parse(input);
            if (x != NULL) {
                x = lval_eval(e, x);
                lval_println(x);
                lval_del(x);
            }
            free(input);
        }

    }

    /* cleanup */
    lenv_del(e);
    free_parser();

    return 0;
}
Esempio n. 15
0
lval* builtin_load(lenv* e, lval* a) {
  LASSERT_NUM("load", a, 1);
  LASSERT_TYPE("load", a, 0, LVAL_STR);

  //Parse file given by string as filename
  mpc_result_t r;
  if (mpc_parse_contents(a->cell[0]->str, blisp, &r)) {
    //Read Contents
    lval* expr = lval_read(r.output);
    mpc_ast_delete(r.output);

    //Evaluate expressions on stack
    while (expr->count) {
      lval* x = lval_eval(e, lval_pop(expr, 0));
      if (x->type == LVAL_ERR) {
        lval_println(x);
      }
      lval_del(x);
    }

    //Delete expression and args
    lval_del(expr);
    lval_del(a);

    //Return empty list
    return lval_sexpr();

  } else {
    //Get error message as string and return as lval_err
    char* err_msg = mpc_err_string(r.error);
    mpc_err_delete(r.error);

    lval* err = lval_err("Could not load Library %s", err_msg);
    free(err_msg);
    lval_del(a);

    //Cleanup and return error
    return err;
  }
}
Esempio n. 16
0
File: lval.c Progetto: tsmarsh/lispy
lval* lval_call(lenv* e, lval* f, lval* a) {

  if (f->builtin) { return f->builtin(e, a); }

  int given = a->count;
  int total = f->formals->count;

  while (a->count) {

    if (f->formals->count == 0) {
      lval_del(a); return lval_err(
        "Function passed too many arguments. "
        "Got %i, Expected %i.", given, total); 
    }

    lval* sym = lval_pop(f->formals, 0);

    lval* val = lval_pop(a, 0);

    lenv_put(f->env, sym, val);

    lval_del(sym); lval_del(val);
  }

  lval_del(a);

  if (f->formals->count == 0) {

    f->env->par = e;

    return builtin_eval(
      f->env, lval_add(lval_sexpr(), lval_copy(f->body)));
  } else {
    return lval_copy(f);
  }
}
Esempio n. 17
0
int main(int argc, char** argv) {
    // Initialization
    parser_init();
    lenv* env = lenv_new();
    builtins_init(env);

    if (argc >= 2) {
        // Loop over file names
        for (int i = 1; i < argc; i++) {
            lval* args   = lval_add(lval_sexpr(), lval_str(argv[i]));
            lval* result = builtin_load(env, args);

            if (result->type == LVAL_ERR) {
                lval_println(env, result);
            }
            lval_del(result);
        }
    } else {
        // Welcome message
        puts("MLisp Version 0.1dev");
        puts("Enter 'quit' to exit\n");

        while (1) {
            char* input = read_input();
            add_history(input);

            if (input == NULL || strstr(input, "exit") || strstr(input, "quit")) {
                puts("Bye!");
                if (input != NULL) {
                    xfree(input);
                }
                break;
            }

            lval* result = NULL;
            mpc_err_t* parser_error = NULL;

            if (parse("<stdin>", input, env, &result, &parser_error)) {
                if (!(result->type == LVAL_SEXPR && result->count == 0)) {
                    char* repr = lval_repr(env, result);
                    printf("%s\n", repr);
                    xfree(repr);
                }

                lval_del(result);
            } else {
                mpc_err_print(parser_error);
                mpc_err_delete(parser_error);
            }

            xfree(input);
        }
    }

    lenv_del(env);

    // Undefine and delete our parsers
    parser_cleanup();

    return 0;
}
lval* lval_call(lenv* e, lval* f, lval* a) {

  /* If Builtin then simply apply that */
  if (f->builtin) { return f->builtin(e, a); }

  /* Record Argument Counts */
  int given = a->count;
  int total = f->formals->count;

  /* While arguments still remain to be processed */
  while (a->count) {

    /* If we've ran out of formal arguments to bind */
    if (f->formals->count == 0) {
      lval_del(a);
      return lval_err("Function passed too many arguments. Got %i, Expected %i.", given, total);
    }

    /* Pop the first symbol from the formals */
    lval* sym = lval_pop(f->formals, 0);

    /* Special Case to deal with '&' */
    if (strcmp(sym->sym, "&") == 0) {

      /* Ensure '&' is followed by another symbol */
      if (f->formals->count != 1) {
        lval_del(a);
        return lval_err("Function format invalid. Symbol '&' not followed by single symbol.");
      }

      /* Next formal should be bound to remaining arguments */
      lval* nsym = lval_pop(f->formals, 0);
      lenv_put(f->env, nsym, builtin_list(e, a));
      lval_del(sym); lval_del(nsym);
      break;
    }

    /* Pop the next argument from the list */
    lval* val = lval_pop(a, 0);

    /* Bind a copy into the function's environment */
    lenv_put(f->env, sym, val);

    /* Delete symbol and value */
    lval_del(sym); lval_del(val);
  }

  /* Argument list is now bound so can be cleaned up */
  lval_del(a);

  /* If '&' remains in formal list it should be bound to empty list */
  if (f->formals->count > 0 &&
    strcmp(f->formals->cell[0]->sym, "&") == 0) {

    /* Check to ensure that & is not passed invalidly. */
    if (f->formals->count != 2) {
      return lval_err("Function format invalid. Symbol '&' not followed by single symbol.");
    }

    /* Pop and delete '&' symbol */
    lval_del(lval_pop(f->formals, 0));

    /* Pop next symbol and create empty list */
    lval* sym = lval_pop(f->formals, 0);
    lval* val = lval_qexpr();

    /* Bind to environment and delete */
    lenv_put(f->env, sym, val);
    lval_del(sym); lval_del(val);
  }

  /* If all formals have been bound evaluate */
  if (f->formals->count == 0) {

    /* Set Function Environment parent to current evaluation Environment */
    f->env->par = e;

    /* Evaluate and return */
    return builtin_eval(f->env, lval_add(lval_sexpr(), lval_copy(f->body)));
  } else {
    /* Otherwise return partially evaluated function */
    return lval_copy(f);
  }

}
Esempio n. 19
0
lval* lval_call(lenv* e, lval* f, lval* a) {
    if (f->builtin) {
        return f->builtin(e, a);
    }

    int given = a->count;
    int total = f->formals->count;

    while (a->count) {
        if (f->formals->count == 0) {
            lval_del(a);
            return lval_err("Function passed too many arguments. Expected %i, Got %i.", total, given);
        }

        lval* sym = lval_pop(f->formals, 0);

        // Variadic operator
        if (strcmp(sym->sym, "&") == 0){
            if (f->formals->count != 1) {
                lval_del(a);
                return lval_err("Function format invalid. "
                        "Symbol '&' not followed by a single symbol");
            }

            lval* nsym = lval_pop(f->formals, 0);
            lenv_put(f->env, nsym, builtin_list(e, a));
            lval_del(sym);
            lval_del(nsym);
            break;
        }

        lval* val = lval_pop(a, 0);
        lenv_put(f->env, sym, val);
        lval_del(val);
        lval_del(sym);
    }

    lval_del(a);

    // If '&' remains in formal list bind to empty list
    if (f->formals->count > 0 &&
            strcmp(f->formals->cell[0]->sym, "&") == 0) {
        if (f->formals->count != 2) {
            return lval_err("Function format invalid. "
                    "Symbol '&' not followed by a single symbol");
        }

        lval_del(lval_pop(f->formals, 0));

        lval* sym = lval_pop(f->formals, 0);
        lval* val = lval_qexpr();

        lenv_put(f->env, sym, val);
        lval_del(val);
        lval_del(sym);
    }

    if (f->formals->count == 0) {
        f->env->par = e;
        return builtin_eval(f->env, lval_add(lval_sexpr(), lval_copy(f->body)));
    } else {
        return lval_copy(f);
    }
}
Esempio n. 20
0
lval *lval_call(lenv *e, lval *f, lval *a)
{
  if (f->builtin)
  {
    return f->builtin(e, a);
  }

  int given = a->count;
  int total = f->formals->count;

  while (a->count)
  {
    if (f->formals->count == 0)
    {
      lval_del(a);
      return lval_err("Function passed too many arguments\n"
        "  got %i expected %i", given, total);
    }
    lval *sym = lval_pop(f->formals, 0);

    if (strcmp(sym->sym, "&") == 0)
    {
      if (f->formals->count != 1)
      {
        lval_del(a);
        return lval_err("Function format invalid\n"
          "  symbol '&' not followed by single symbol");
      }
      lval *nsym = lval_pop(f->formals, 0);
      lenv_put(f->env, nsym, builtin_list(e, a));
      lval_del(sym);
      lval_del(nsym);
      break;
    }

    lval *val = lval_pop(a, 0);
    lenv_put(f->env, sym, val);
    lval_del(sym);
    lval_del(val);
  }
  lval_del(a);

  if (f->formals->count > 0 && strcmp(f->formals->cell[0]->sym, "&") == 0)
  {
    if (f->formals->count != 2)
    {
      return lval_err("Function format invalid\n"
        "  symbol '&' not followed by single symbol");
    }

    lval_del(lval_pop(f->formals, 0));
    lval *sym = lval_pop(f->formals, 0);
    lval *val = lval_qexpr();
    lval_del(sym);
    lval_del(val);
  }

  if (f->formals->count == 0)
  {
    f->env->par = e;
    return builtin_eval(f->env, lval_add(lval_sexpr(), lval_copy(f->body)));
  }
  else
  {
    return lval_copy(f);
  }
}
Esempio n. 21
0
File: eval.c Progetto: tevino/aroma
lval *lval_call(lenv *e, lval *f, lval *a){
    if (f->builtin){ return f->builtin(e, a); }

    int given = a->count;
    int required = f->formals->count;

    while (a->count){
        if (f->formals->count == 0){
            lval_del(a);
            return lval_err("Function passed too many arguments."
                            "Expected %d, got %d.", required, given);
        }

        lval *sym = lval_pop(f->formals, 0);

        if (strcmp(sym->sym, "&") == 0){
            /* Ensure & is followed by another symbol */
            if (f->formals->count != 1){
                lval_del(a);
                return lval_err("& not followed by single symbol");
            }

            /* Bound next formal to remaining arguments */
            lval *nsym = lval_pop(f->formals, 0);
            lenv_set(f->env, nsym, builtin_list(e, a));
            lval_del(sym);
            lval_del(nsym);
            break;
        }

        /* Take out the argument */
        lval *val = lval_pop(a, 0);

        /* Bound to sym */
        lenv_set(f->env, sym, val);

        lval_del(sym);
        lval_del(val);
    }

    lval_del(a);

    /* If & remaining in argument list, bound to () */
    if (f->formals->count > 0 && 
        strcmp(f->formals->cell[0]->sym, "&") == 0){

        /* Ensure & is not passed invalidly */
        if(f->formals->count != 2){
            return lval_err("& not followed by single symbol");
        }

        /* Delete & */
        lval_del(lval_pop(f->formals, 0));

        /* pop next formal */
        lval *sym = lval_pop(f->formals, 0);

        lval *empty = lval_qexpr();

        lenv_set(f->env, sym, empty);
        lval_del(sym);
        lval_del(empty);
    }


    if (f->formals->count == 0){
        f->env->parent = e;

        return builtin_eval(f->env, lval_add(lval_sexpr(), lval_copy(f->body)));
    } else {
        return lval_copy(f);
    }
}
Esempio n. 22
0
lval* builtin_env(lenv* e, lval* a) {
  lenv_iter(e);
  return lval_sexpr();
}