diff options
Diffstat (limited to 'node_modules/fastparse/lib/Parser.js')
-rw-r--r-- | node_modules/fastparse/lib/Parser.js | 108 |
1 files changed, 108 insertions, 0 deletions
diff --git a/node_modules/fastparse/lib/Parser.js b/node_modules/fastparse/lib/Parser.js new file mode 100644 index 0000000..7f47c58 --- /dev/null +++ b/node_modules/fastparse/lib/Parser.js @@ -0,0 +1,108 @@ +/* + MIT License http://www.opensource.org/licenses/mit-license.php + Author Tobias Koppers @sokra +*/ + +function ignoreFunction() {} + +function createReturningFunction(value) { + return function() { + return value; + }; +} + +function Parser(states) { + this.states = this.compileStates(states); +} + +Parser.prototype.compileStates = function(states) { + var result = {}; + Object.keys(states).forEach(function(name) { + result[name] = this.compileState(states[name], states); + }, this); + return result; +}; + +Parser.prototype.compileState = function(state, states) { + var regExps = []; + function iterator(str, value) { + regExps.push({ + groups: Parser.getGroupCount(str), + regExp: str, + value: value + }); + } + function processState(statePart) { + if(Array.isArray(statePart)) { + statePart.forEach(processState); + } else if(typeof statePart === "object") { + Object.keys(statePart).forEach(function(key) { + iterator(key, statePart[key]); + }); + } else if(typeof statePart === "string") { + processState(states[statePart]); + } else { + throw new Error("Unexpected 'state' format"); + } + } + processState(state); + var total = regExps.map(function(r) { + return "(" + r.regExp + ")"; + }).join("|"); + var actions = []; + var pos = 1; + regExps.forEach(function(r) { + var fn; + if(typeof r.value === "function") { + fn = r.value; + } else if(typeof r.value === "string") { + fn = createReturningFunction(r.value); + } else { + fn = ignoreFunction; + } + actions.push({ + name: r.regExp, + fn: fn, + pos: pos, + pos2: pos + r.groups + 1 + }); + pos += r.groups + 1; + }); + return { + regExp: new RegExp(total, "g"), + actions: actions + }; +}; + +Parser.getGroupCount = function(regExpStr) { + return new RegExp("(" + regExpStr + ")|^$").exec("").length - 2; +}; + +Parser.prototype.parse = function(initialState, string, context) { + context = context || {}; + var currentState = initialState; + var currentIndex = 0; + for(;;) { + var state = this.states[currentState]; + var regExp = state.regExp; + regExp.lastIndex = currentIndex; + var match = regExp.exec(string); + if(!match) return context; + var actions = state.actions; + currentIndex = state.regExp.lastIndex; + for(var i = 0; i < actions.length; i++) { + var action = actions[i]; + if(match[action.pos]) { + var ret = action.fn.apply(context, Array.prototype.slice.call(match, action.pos, action.pos2).concat([state.regExp.lastIndex - match[0].length, match[0].length])); + if(ret) { + if(!(ret in this.states)) + throw new Error("State '" + ret + "' doesn't exist"); + currentState = ret; + } + break; + } + } + } +}; + +module.exports = Parser; |