parse_utils.js

(function ($B) {
    "use strict";
    var _b_ = $B.builtins

    $B._PyPegen_lookahead = function(p, positive, rule) {
        let mark = p.mark;
        let res = rule.apply(p);
        p.mark = mark;
        return (res != null) == positive;
    }

    $B._PyPegen_lookahead_with_arg = function (p, positive, rule, target, arg) {
        let mark = p.mark;
        let res;
        if (target != null) {
            res = rule(target, arg)
        } else {
            res = rule.apply(p, [arg]);
        }
        p.mark = mark;
        return (res != null) == positive;
    }

    $B._PyPegen_expect_token = function(p, type) {
        if (p.mark == p.fill) {
            if ($B._PyPegen_fill_token(p) < 0) {
                p.error_indicator = 1;
                return null;
            }
        }
        let t = p.tokens[p.mark];
        // console.log(t, type);
        if (t.type == 'NUMBER' && type == 'NUMBER') {
            p.mark += 1;
            return t;
        }
        if (t.string != type) {
            return null;
        }
        p.mark += 1;
        return t;
    }

    $B._PyPegen_is_memoized = function (p, type) {
        if (p.mark == p.fill) {
            if ($B._PyPegen_fill_token(p) < 0) {
                p.error_indicator = 1;
                return null;
            }
        }
        let t = p.tokens[p.mark];
        if (t.memo == null) {
            return [null, false]
        }
        if (t.memo[type] === undefined) {
            return [null, false]
        }
        return [t.memo[type], true];
    }

    $B._PyPegen_insert_memo = $B._PyPegen_update_memo = function (p, mark, type, value) {
        let t = p.tokens[mark];
        if (t.memo == null) {
            t.memo = {};
        }
        return t.memo[type] = value;
    }

    $B._PyPegen_name_from_token = function (p, t) {
        throw new Error('fail for now');
    }

    // expr_ty
    // _PyPegen_name_token(Parser * p)
    // {
    //     Token * t = _PyPegen_expect_token(p, NAME);
    //     return _PyPegen_name_from_token(p, t);
    // }

    $B._PyPegen_expect_soft_keyword = function(p, keyword) {
        if (p.mark == p.fill) {
            if ($B._PyPegen_fill_token(p) < 0) {
                p.error_indicator = 1;
                return null;
            }
        }
        let t = p.tokens[p.mark];
        if (t.type != 'NAME') {
            return null;
        }
        if (t.string == keyword) {
            p.mark += 1;
            return t;
        }
        return null;
    }

    $B._PyPegen_fill_token = function(p) {
        while (true) {
            var next = p.tokenizer.next();
            if (!next.done) {
                var value = next.value;
                if (!['ENCODING', 'NL', 'COMMENT'].includes(value.type)) {
                    p.tokens.push(value);
                    p.fill += 1;
                    break;
                }
            } else {
                throw Error('tokenizer exhausted')
            }
        }
        return 1;
    }
})(__BRYTHON__)