@masala/parser
Version:
137 lines (112 loc) • 8.46 kB
JavaScript
;
Object.defineProperty(exports, "__esModule", {
value: true
});
var _createClass = function () { function defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ("value" in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } } return function (Constructor, protoProps, staticProps) { if (protoProps) defineProperties(Constructor.prototype, protoProps); if (staticProps) defineProperties(Constructor, staticProps); return Constructor; }; }();
var _stream = require('./stream');
var _stream2 = _interopRequireDefault(_stream);
var _option = require('../data/option');
var _option2 = _interopRequireDefault(_option);
function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }
function _possibleConstructorReturn(self, call) { if (!self) { throw new ReferenceError("this hasn't been initialised - super() hasn't been called"); } return call && (typeof call === "object" || typeof call === "function") ? call : self; }
function _inherits(subClass, superClass) { if (typeof superClass !== "function" && superClass !== null) { throw new TypeError("Super expression must either be null or a function, not " + typeof superClass); } subClass.prototype = Object.create(superClass && superClass.prototype, { constructor: { value: subClass, enumerable: false, writable: true, configurable: true } }); if (superClass) Object.setPrototypeOf ? Object.setPrototypeOf(subClass, superClass) : subClass.__proto__ = superClass; } /*
* Parsec
* https://github.com/d-plaindoux/parsec
*
* Copyright (c) 2016 Didier Plaindoux
* Licensed under the LGPL2 license.
*/
/**
* ParserStream stream class
* Compared to StringStream, it is NOT a RandomAccess.
* You must use a substream before making an access to a unreached point.
*/
var ParserStream = function (_Stream) {
_inherits(ParserStream, _Stream);
function ParserStream(parser, lowerStream) {
_classCallCheck(this, ParserStream);
//TODO: why the parser is called source ?
var _this = _possibleConstructorReturn(this, (ParserStream.__proto__ || Object.getPrototypeOf(ParserStream)).call(this));
_this.source = parser;
_this.input = lowerStream;
_this.offsets = [0];
return _this;
}
_createClass(ParserStream, [{
key: 'getOffset',
value: function getOffset(index) {
if (index < this.offsets.length) {
// TODO logger console.log('found offset', this.offsets[index]);
return _option2.default.some(this.offsets[index]);
}
return _option2.default.none();
}
// Stream 'a => number -> number
}, {
key: 'location',
value: function location(index) {
if (index === 0) {
return 0;
}
var option = this.getOffset(index);
if (option.isPresent()) {
// TODO: check the +1 ; the -1 has disappeared
return this.input.location(option.get());
} else {
// TODO logger
throw 'No location has been found yet for index ' + index;
// TODO: What is the use case ?
// return this.input.location(this.getOffset(index - 1) + 1);
}
}
// ParserStream 'a => unit -> boolean
}, {
key: 'endOfStream',
value: function endOfStream(index) {
var option = this.getOffset(index);
if (option.isPresent()) {
return this.input.endOfStream(option.get());
} else {
// If last was the last befor end of stream, then yes
var last = this.offsets[this.offsets.length - 1];
return this.input.endOfStream(last + 1);
}
}
// ParserStream 'a => number -> 'a <+> error
/**
* index is the token index ; It uses getOffset(index) to retrieve the location
* in the stringStream
* @param index token index
*/
}, {
key: 'unsafeGet',
value: function unsafeGet(index) {
// the wrapped parser parses the StringStream
var sourceIndex = void 0;
var option = this.getOffset(index);
if (option.isPresent()) {
// we have already read it. Should be caught by the bufferedStream
sourceIndex = option.get();
} else {
// TODO logger
throw new Error();
}
var result = this.source.parse(this.input, sourceIndex);
if (result.isAccepted()) {
// Why index+1 ? Because we succeeded, and the source is at result.offset
this.offsets.push(result.offset);
return result.value;
} else {
// TODO logger
throw new Error();
}
}
}]);
return ParserStream;
}(_stream2.default);
function factory(parser, lowerStream) {
return new ParserStream(parser, lowerStream);
}
exports.default = factory;
//# sourceMappingURL=parserstream.js.map