Time slots app prototype
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// Jison, an LR(0), SLR(1), LARL(1), LR(1) Parser Generator
// Zachary Carter <zach@carter.name>
// MIT X Licensed
var typal = require('./util/typal').typal;
var Set = require('./util/set').Set;
var Jison = exports.Jison = exports;
// detect print
if (typeof console !== 'undefined' && console.log) {
Jison.print = console.log;
} else if (typeof puts !== 'undefined') {
Jison.print = function print () { puts([].join.call(arguments, ' ')); };
} else if (typeof print !== 'undefined') {
Jison.print = print;
} else {
Jison.print = function print () {};
}
Jison.Parser = (function () {
// iterator utility
function each (obj, func) {
if (obj.forEach) {
obj.forEach(func);
} else {
var p;
for (p in obj) {
if (obj.hasOwnProperty(p)) {
func.call(obj, obj[p], p, obj);
}
}
}
}
var Nonterminal = typal.construct({
constructor: function Nonterminal (symbol) {
this.symbol = symbol;
this.productions = new Set();
this.first = [];
this.follows = [];
this.nullable = false;
},
toString: function Nonterminal_toString () {
var str = this.symbol+"\n";
str += (this.nullable ? 'nullable' : 'not nullable');
str += "\nFirsts: "+this.first.join(', ');
str += "\nFollows: "+this.first.join(', ');
str += "\nProductions:\n "+this.productions.join('\n ');
return str;
}
});
var Production = typal.construct({
constructor: function Production (symbol, handle, id) {
this.symbol = symbol;
this.handle = handle;
this.nullable = false;
this.id = id;
this.first = [];
this.precedence = 0;
},
toString: function Production_toString () {
return this.symbol+" -> "+this.handle.join(' ');
}
});
var generator = typal.beget();
generator.constructor = function Jison_Generator (grammar, opt) {
var options = typal.mix.call({}, grammar.options, opt);
this.terms = {};
this.operators = {};
this.productions = [];
this.conflicts = 0;
this.resolutions = [];
this.options = options;
this.parseParams = grammar.parseParams;
this.yy = {}; // accessed as yy free variable in the parser/lexer actions
// source included in semantic action execution scope
if (grammar.actionInclude) {
if (typeof grammar.actionInclude === 'function') {
grammar.actionInclude = String(grammar.actionInclude).replace(/^\s*function \(\) \{/, '').replace(/\}\s*$/, '');
}
this.actionInclude = grammar.actionInclude;
}
this.moduleInclude = grammar.moduleInclude || '';
this.DEBUG = options.debug || false;
if (this.DEBUG) this.mix(generatorDebug); // mixin debug methods
this.processGrammar(grammar);
};
generator.processGrammar = function processGrammarDef (grammar) {
var bnf = grammar.bnf,
tokens = grammar.tokens,
nonterminals = this.nonterminals = {},
productions = this.productions,
self = this;
if (tokens) {
if (typeof tokens === 'string') {
tokens = tokens.trim().split(' ');
} else {
tokens = tokens.slice(0);
}
}
var symbols = this.symbols = [];
// calculate precedence of operators
var operators = this.operators = processOperators(grammar.operators);
// build productions from cfg
this.buildProductions(bnf, productions, nonterminals, symbols, operators);
if (tokens && this.terminals.length !== tokens.length) {
self.trace("Warning: declared tokens differ from tokens found in rules.");
self.trace(this.terminals);
self.trace(tokens);
}
// augment the grammar
this.augmentGrammar(grammar);
};
generator.augmentGrammar = function augmentGrammar (grammar) {
if (this.productions.length === 0) {
throw new Error("Grammar error: must have at least one rule.");
}
// use specified start symbol, or default to first user defined production
this.startSymbol = grammar.start || grammar.startSymbol || this.productions[0].symbol;
if (!this.nonterminals[this.startSymbol]) {
throw new Error("Grammar error: startSymbol must be a non-terminal found in your grammar.");
}
this.EOF = "$end";
// augment the grammar
var acceptProduction = new Production('$accept', [this.startSymbol, '$end'], 0);
this.productions.unshift(acceptProduction);
// prepend parser tokens
this.symbols.unshift("$accept",this.EOF);
this.symbols_.$accept = 0;
this.symbols_[this.EOF] = 1;
this.terminals.unshift(this.EOF);
this.nonterminals.$accept = new Nonterminal("$accept");
this.nonterminals.$accept.productions.push(acceptProduction);
// add follow $ to start symbol
this.nonterminals[this.startSymbol].follows.push(this.EOF);
};
// set precedence and associativity of operators
function processOperators (ops) {
if (!ops) return {};
var operators = {};
for (var i=0,k,prec;prec=ops[i]; i++) {
for (k=1;k < prec.length;k++) {
operators[prec[k]] = {precedence: i+1, assoc: prec[0]};
}
}
return operators;
}
generator.buildProductions = function buildProductions(bnf, productions, nonterminals, symbols, operators) {
// Because of the switch limits in v8 this should probably be split into several methods for the different ranges
var actions = [
'/* self == yyval */',
this.actionInclude || '',
'var $0 = $$.length - 1;',
'switch (yystate) {'
];
var actionGroups = {};
var prods, symbol;
var productions_ = [0];
var symbolId = 1;
var symbols_ = {};
var her = false; // has error recovery
function addSymbol (s) {
if (s && !symbols_[s]) {
symbols_[s] = ++symbolId;
symbols.push(s);
}
}
// add error symbol; will be third symbol, or "2" ($accept, $end, error)
addSymbol("error");
for (symbol in bnf) {
if (!bnf.hasOwnProperty(symbol)) continue;
addSymbol(symbol);
nonterminals[symbol] = new Nonterminal(symbol);
if (typeof bnf[symbol] === 'string') {
prods = bnf[symbol].split(/\s*\|\s*/g);
} else {
prods = bnf[symbol].slice(0);
}
prods.forEach(buildProduction);
}
for (var action in actionGroups)
actions.push(actionGroups[action].join(' '), action, 'break;');
var sym, terms = [], terms_ = {};
each(symbols_, function (id, sym) {
if (!nonterminals[sym]) {
terms.push(sym);
terms_[id] = sym;
}
});
this.hasErrorRecovery = her;
this.terminals = terms;
this.terminals_ = terms_;
this.symbols_ = symbols_;
this.productions_ = productions_;
actions.push('}');
actions = actions.join("\n")
.replace(/YYABORT/g, 'return false')
.replace(/YYACCEPT/g, 'return true');
var yyvalParam = "this";
var parameters = "self, yytext, yy, yystate /* action[1] */, $$ /* vstack */";
if (this.parseParams) parameters += ', ' + this.parseParams.join(', ');
this.performAction = "function performAction(" + parameters + ") {\n" + actions + "\n}";
function buildProduction (handle) {
var r, rhs, i;
if (handle.constructor === Array) {
rhs = (typeof handle[0] === 'string') ?
handle[0].trim().split(' ') :
handle[0].slice(0);
for (i=0; i<rhs.length; i++) {
if (rhs[i] === 'error') her = true;
if (!symbols_[rhs[i]]) {
addSymbol(rhs[i]);
}
}
if (typeof handle[1] === 'string' || handle.length == 3) {
// semantic action specified
var label = 'case ' + (productions.length+1) + ':', action = handle[1];
// replace named semantic values ($nonterminal)
if (action.match(/[$@][a-zA-Z][a-zA-Z0-9_]*/)) {
var count = {},
names = {};
for (i=0;i<rhs.length;i++) {
// check for aliased names, e.g., id[alias]
var rhs_i = rhs[i].match(/\[[a-zA-Z][a-zA-Z0-9_-]*\]/);
if (rhs_i) {
rhs_i = rhs_i[0].substr(1, rhs_i[0].length-2);
rhs[i] = rhs[i].substr(0, rhs[i].indexOf('['));
} else {
rhs_i = rhs[i];
}
if (names[rhs_i]) {
names[rhs_i + (++count[rhs_i])] = i+1;
} else {
names[rhs_i] = i+1;
names[rhs_i + "1"] = i+1;
count[rhs_i] = 1;
}
}
action = action.replace(/\$([a-zA-Z][a-zA-Z0-9_]*)/g, function (str, pl) {
return names[pl] ? '$'+names[pl] : str;
}).replace(/@([a-zA-Z][a-zA-Z0-9_]*)/g, function (str, pl) {
return names[pl] ? '@'+names[pl] : str;
});
}
action = action
// replace references to $$ with this.$, and @$ with this._$
.replace(/([^'"])\$\$|^\$\$/g, '$1self.$').replace(/@[0$]/g, "self._$")
// replace semantic value references ($n) with stack value (stack[n])
.replace(/\$(-?\d+)/g, function (_, n) {
return "$$[$0" + (parseInt(n, 10) - rhs.length || '') + "]";
})
// same as above for location references (@n)
.replace(/@(-?\d+)/g, function (_, n) {
return "_$[$0" + (n - rhs.length || '') + "]";
});
if (action in actionGroups) actionGroups[action].push(label);
else actionGroups[action] = [label];
// done with aliases; strip them.
rhs = rhs.map(function(e,i) { return e.replace(/\[[a-zA-Z_][a-zA-Z0-9_-]*\]/g, '') });
r = new Production(symbol, rhs, productions.length+1);
// precedence specified also
if (handle[2] && operators[handle[2].prec]) {
r.precedence = operators[handle[2].prec].precedence;
}
} else {
// no action -> don't care about aliases; strip them.
rhs = rhs.map(function(e,i) { return e.replace(/\[[a-zA-Z_][a-zA-Z0-9_-]*\]/g, '') });
// only precedence specified
r = new Production(symbol, rhs, productions.length+1);
if (operators[handle[1].prec]) {
r.precedence = operators[handle[1].prec].precedence;
}
}
} else {
// no action -> don't care about aliases; strip them.
handle = handle.replace(/\[[a-zA-Z_][a-zA-Z0-9_-]*\]/g, '');
rhs = handle.trim().split(' ');
for (i=0; i<rhs.length; i++) {
if (rhs[i] === 'error') her = true;
if (!symbols_[rhs[i]]) {
addSymbol(rhs[i]);
}
}
r = new Production(symbol, rhs, productions.length+1);
}
if (r.precedence === 0) {
// set precedence
for (i=r.handle.length-1; i>=0; i--) {
if (!(r.handle[i] in nonterminals) && r.handle[i] in operators) {
r.precedence = operators[r.handle[i]].precedence;
}
}
}
productions.push(r);
productions_.push([symbols_[r.symbol], r.handle[0] === '' ? 0 : r.handle.length]);
nonterminals[symbol].productions.push(r);
}
};
generator.createParser = function createParser () {
throw new Error('Calling abstract method.');
};
// noop. implemented in debug mixin
generator.trace = function trace () { };
generator.warn = function warn () {
var args = Array.prototype.slice.call(arguments,0);
Jison.print.call(null,args.join(""));
};
generator.error = function error (msg) {
throw new Error(msg);
};
// Generator debug mixin
var generatorDebug = {
trace: function trace () {
Jison.print.apply(null, arguments);
},
beforeprocessGrammar: function () {
this.trace("Processing grammar.");
},
afteraugmentGrammar: function () {
var trace = this.trace;
each(this.symbols, function (sym, i) {
trace(sym+"("+i+")");
});
}
};
/*
* Mixin for common behaviors of lookahead parsers
* */
var lookaheadMixin = {};
lookaheadMixin.computeLookaheads = function computeLookaheads () {
if (this.DEBUG) this.mix(lookaheadDebug); // mixin debug methods
this.computeLookaheads = function () {};
this.nullableSets();
this.firstSets();
this.followSets();
};
// calculate follow sets typald on first and nullable
lookaheadMixin.followSets = function followSets () {
var productions = this.productions,
nonterminals = this.nonterminals,
self = this,
cont = true;
// loop until no further changes have been made
while(cont) {
cont = false;
productions.forEach(function Follow_prod_forEach (production, k) {
//self.trace(production.symbol,nonterminals[production.symbol].follows);
// q is used in Simple LALR algorithm determine follows in context
var q;
var ctx = !!self.go_;
var set = [],oldcount;
for (var i=0,t;t=production.handle[i];++i) {
if (!nonterminals[t]) continue;
// for Simple LALR algorithm, self.go_ checks if
if (ctx)
q = self.go_(production.symbol, production.handle.slice(0, i));
var bool = !ctx || q === parseInt(self.nterms_[t], 10);
if (i === production.handle.length+1 && bool) {
set = nonterminals[production.symbol].follows;
} else {
var part = production.handle.slice(i+1);
set = self.first(part);
if (self.nullable(part) && bool) {
set.push.apply(set, nonterminals[production.symbol].follows);
}
}
oldcount = nonterminals[t].follows.length;
Set.union(nonterminals[t].follows, set);
if (oldcount !== nonterminals[t].follows.length) {
cont = true;
}
}
});
}
};
// return the FIRST set of a symbol or series of symbols
lookaheadMixin.first = function first (symbol) {
// epsilon
if (symbol === '') {
return [];
// RHS
} else if (symbol instanceof Array) {
var firsts = [];
for (var i=0,t;t=symbol[i];++i) {
if (!this.nonterminals[t]) {
if (firsts.indexOf(t) === -1)
firsts.push(t);
} else {
Set.union(firsts, this.nonterminals[t].first);
}
if (!this.nullable(t))
break;
}
return firsts;
// terminal
} else if (!this.nonterminals[symbol]) {
return [symbol];
// nonterminal
} else {
return this.nonterminals[symbol].first;
}
};
// fixed-point calculation of FIRST sets
lookaheadMixin.firstSets = function firstSets () {
var productions = this.productions,
nonterminals = this.nonterminals,
self = this,
cont = true,
symbol,firsts;
// loop until no further changes have been made
while(cont) {
cont = false;
productions.forEach(function FirstSets_forEach (production, k) {
var firsts = self.first(production.handle);
if (firsts.length !== production.first.length) {
production.first = firsts;
cont=true;
}
});
for (symbol in nonterminals) {
firsts = [];
nonterminals[symbol].productions.forEach(function (production) {
Set.union(firsts, production.first);
});
if (firsts.length !== nonterminals[symbol].first.length) {
nonterminals[symbol].first = firsts;
cont=true;
}
}
}
};
// fixed-point calculation of NULLABLE
lookaheadMixin.nullableSets = function nullableSets () {
var firsts = this.firsts = {},
nonterminals = this.nonterminals,
self = this,
cont = true;
// loop until no further changes have been made
while(cont) {
cont = false;
// check if each production is nullable
this.productions.forEach(function (production, k) {
if (!production.nullable) {
for (var i=0,n=0,t;t=production.handle[i];++i) {
if (self.nullable(t)) n++;
}
if (n===i) { // production is nullable if all tokens are nullable
production.nullable = cont = true;
}
}
});
//check if each symbol is nullable
for (var symbol in nonterminals) {
if (!this.nullable(symbol)) {
for (var i=0,production;production=nonterminals[symbol].productions.item(i);i++) {
if (production.nullable)
nonterminals[symbol].nullable = cont = true;
}
}
}
}
};
// check if a token or series of tokens is nullable
lookaheadMixin.nullable = function nullable (symbol) {
// epsilon
if (symbol === '') {
return true;
// RHS
} else if (symbol instanceof Array) {
for (var i=0,t;t=symbol[i];++i) {
if (!this.nullable(t))
return false;
}
return true;
// terminal
} else if (!this.nonterminals[symbol]) {
return false;
// nonterminal
} else {
return this.nonterminals[symbol].nullable;
}
};
// lookahead debug mixin
var lookaheadDebug = {
beforenullableSets: function () {
this.trace("Computing Nullable sets.");
},
beforefirstSets: function () {
this.trace("Computing First sets.");
},
beforefollowSets: function () {
this.trace("Computing Follow sets.");
},
afterfollowSets: function () {
var trace = this.trace;
each(this.nonterminals, function (nt, t) {
trace(nt, '\n');
});
}
};
/*
* Mixin for common LR parser behavior
* */
var lrGeneratorMixin = {};
lrGeneratorMixin.buildTable = function buildTable () {
if (this.DEBUG) this.mix(lrGeneratorDebug); // mixin debug methods
this.states = this.canonicalCollection();
this.table = this.parseTable(this.states);
this.defaultActions = findDefaults(this.table);
};
lrGeneratorMixin.Item = typal.construct({
constructor: function Item(production, dot, f, predecessor) {
this.production = production;
this.dotPosition = dot || 0;
this.follows = f || [];
this.predecessor = predecessor;
this.id = parseInt(production.id+'a'+this.dotPosition, 36);
this.markedSymbol = this.production.handle[this.dotPosition];
},
remainingHandle: function () {
return this.production.handle.slice(this.dotPosition+1);
},
eq: function (e) {
return e.id === this.id;
},
handleToString: function () {
var handle = this.production.handle.slice(0);
handle[this.dotPosition] = '.'+(handle[this.dotPosition]||'');
return handle.join(' ');
},
toString: function () {
var temp = this.production.handle.slice(0);
temp[this.dotPosition] = '.'+(temp[this.dotPosition]||'');
return this.production.symbol+" -> "+temp.join(' ') +
(this.follows.length === 0 ? "" : " #lookaheads= "+this.follows.join(' '));
}
});
lrGeneratorMixin.ItemSet = Set.prototype.construct({
afterconstructor: function () {
this.reductions = [];
this.goes = {};
this.edges = {};
this.shifts = false;
this.inadequate = false;
this.hash_ = {};
for (var i=this._items.length-1;i >=0;i--) {
this.hash_[this._items[i].id] = true; //i;
}
},
concat: function concat (set) {
var a = set._items || set;
for (var i=a.length-1;i >=0;i--) {
this.hash_[a[i].id] = true; //i;
}
this._items.push.apply(this._items, a);
return this;
},
push: function (item) {
this.hash_[item.id] = true;
return this._items.push(item);
},
contains: function (item) {
return this.hash_[item.id];
},
valueOf: function toValue () {
var v = this._items.map(function (a) {return a.id;}).sort().join('|');
this.valueOf = function toValue_inner() {return v;};
return v;
}
});
lrGeneratorMixin.closureOperation = function closureOperation (itemSet /*, closureSet*/) {
var closureSet = new this.ItemSet();
var self = this;
var set = itemSet,
itemQueue, syms = {};
do {
itemQueue = new Set();
closureSet.concat(set);
set.forEach(function CO_set_forEach (item) {
var symbol = item.markedSymbol;
// if token is a non-terminal, recursively add closures
if (symbol && self.nonterminals[symbol]) {
if(!syms[symbol]) {
self.nonterminals[symbol].productions.forEach(function CO_nt_forEach (production) {
var newItem = new self.Item(production, 0);
if(!closureSet.contains(newItem))
itemQueue.push(newItem);
});
syms[symbol] = true;
}
} else if (!symbol) {
// reduction
closureSet.reductions.push(item);
closureSet.inadequate = closureSet.reductions.length > 1 || closureSet.shifts;
} else {
// shift
closureSet.shifts = true;
closureSet.inadequate = closureSet.reductions.length > 0;
}
});
set = itemQueue;
} while (!itemQueue.isEmpty());
return closureSet;
};
lrGeneratorMixin.gotoOperation = function gotoOperation (itemSet, symbol) {
var gotoSet = new this.ItemSet(),
self = this;
itemSet.forEach(function goto_forEach(item, n) {
if (item.markedSymbol === symbol) {
gotoSet.push(new self.Item(item.production, item.dotPosition+1, item.follows, n));
}
});
return gotoSet.isEmpty() ? gotoSet : this.closureOperation(gotoSet);
};
/* Create unique set of item sets
* */
lrGeneratorMixin.canonicalCollection = function canonicalCollection () {
var item1 = new this.Item(this.productions[0], 0, [this.EOF]);
var firstState = this.closureOperation(new this.ItemSet(item1)),
states = new Set(firstState),
marked = 0,
self = this,
itemSet;
states.has = {};
states.has[firstState] = 0;
while (marked !== states.size()) {
itemSet = states.item(marked); marked++;
itemSet.forEach(function CC_itemSet_forEach (item) {
if (item.markedSymbol && item.markedSymbol !== self.EOF)
self.canonicalCollectionInsert(item.markedSymbol, itemSet, states, marked-1);
});
}
return states;
};
// Pushes a unique state into the que. Some parsing algorithms may perform additional operations
lrGeneratorMixin.canonicalCollectionInsert = function canonicalCollectionInsert (symbol, itemSet, states, stateNum) {
var g = this.gotoOperation(itemSet, symbol);
if (!g.predecessors)
g.predecessors = {};
// add g to que if not empty or duplicate
if (!g.isEmpty()) {
var gv = g.valueOf(),
i = states.has[gv];
if (i === -1 || typeof i === 'undefined') {
states.has[gv] = states.size();
itemSet.edges[symbol] = states.size(); // store goto transition for table
states.push(g);
g.predecessors[symbol] = [stateNum];
} else {
itemSet.edges[symbol] = i; // store goto transition for table
states.item(i).predecessors[symbol].push(stateNum);
}
}
};
var NONASSOC = 0;
lrGeneratorMixin.parseTable = function parseTable (itemSets) {
var states = [],
nonterminals = this.nonterminals,
operators = this.operators,
conflictedStates = {}, // array of [state, token] tuples
self = this,
s = 1, // shift
r = 2, // reduce
a = 3; // accept
// for each item set
itemSets.forEach(function (itemSet, k) {
var state = states[k] = {};
var action, stackSymbol;
// set shift and goto actions
for (stackSymbol in itemSet.edges) {
itemSet.forEach(function (item, j) {
// find shift and goto actions
if (item.markedSymbol == stackSymbol) {
var gotoState = itemSet.edges[stackSymbol];
if (nonterminals[stackSymbol]) {
// store state to go to after a reduce
//self.trace(k, stackSymbol, 'g'+gotoState);
state[self.symbols_[stackSymbol]] = gotoState;
} else {
//self.trace(k, stackSymbol, 's'+gotoState);
state[self.symbols_[stackSymbol]] = [s,gotoState];
}
}
});
}
// set accept action
itemSet.forEach(function (item, j) {
if (item.markedSymbol == self.EOF) {
// accept
state[self.symbols_[self.EOF]] = [a];
//self.trace(k, self.EOF, state[self.EOF]);
}
});
var allterms = self.lookAheads ? false : self.terminals;
// set reductions and resolve potential conflicts
itemSet.reductions.forEach(function (item, j) {
// if parser uses lookahead, only enumerate those terminals
var terminals = allterms || self.lookAheads(itemSet, item);
terminals.forEach(function (stackSymbol) {
action = state[self.symbols_[stackSymbol]];
var op = operators[stackSymbol];
// Reading a terminal and current position is at the end of a production, try to reduce
if (action || action && action.length) {
var sol = resolveConflict(item.production, op, [r,item.production.id], action[0] instanceof Array ? action[0] : action);
self.resolutions.push([k,stackSymbol,sol]);
if (sol.bydefault) {
self.conflicts++;
if (!self.DEBUG) {
self.warn('Conflict in grammar: multiple actions possible when lookahead token is ',stackSymbol,' in state ',k, "\n- ", printAction(sol.r, self), "\n- ", printAction(sol.s, self));
conflictedStates[k] = true;
}
if (self.options.noDefaultResolve) {
if (!(action[0] instanceof Array))
action = [action];
action.push(sol.r);
}
} else {
action = sol.action;
}
} else {
action = [r,item.production.id];
}
if (action && action.length) {
state[self.symbols_[stackSymbol]] = action;
} else if (action === NONASSOC) {
state[self.symbols_[stackSymbol]] = undefined;
}
});
});
});
if (!self.DEBUG && self.conflicts > 0) {
self.warn("\nStates with conflicts:");
each(conflictedStates, function (val, state) {
self.warn('State '+state);
self.warn(' ',itemSets.item(state).join("\n "));
});
}
return states;
};
// find states with only one action, a reduction
function findDefaults (states) {
var defaults = {};
states.forEach(function (state, k) {
var i = 0;
for (var act in state) {
if ({}.hasOwnProperty.call(state, act)) i++;
}
if (i === 1 && state[act][0] === 2) {
// only one action in state and it's a reduction
defaults[k] = state[act];
}
});
return defaults;
}
// resolves shift-reduce and reduce-reduce conflicts
function resolveConflict (production, op, reduce, shift) {
var sln = {production: production, operator: op, r: reduce, s: shift},
s = 1, // shift
r = 2, // reduce
a = 3; // accept
if (shift[0] === r) {
sln.msg = "Resolve R/R conflict (use first production declared in grammar.)";
sln.action = shift[1] < reduce[1] ? shift : reduce;
if (shift[1] !== reduce[1]) sln.bydefault = true;
return sln;
}
if (production.precedence === 0 || !op) {
sln.msg = "Resolve S/R conflict (shift by default.)";
sln.bydefault = true;
sln.action = shift;
} else if (production.precedence < op.precedence ) {
sln.msg = "Resolve S/R conflict (shift for higher precedent operator.)";
sln.action = shift;
} else if (production.precedence === op.precedence) {
if (op.assoc === "right" ) {
sln.msg = "Resolve S/R conflict (shift for right associative operator.)";
sln.action = shift;
} else if (op.assoc === "left" ) {
sln.msg = "Resolve S/R conflict (reduce for left associative operator.)";
sln.action = reduce;
} else if (op.assoc === "nonassoc" ) {
sln.msg = "Resolve S/R conflict (no action for non-associative operator.)";
sln.action = NONASSOC;
}
} else {
sln.msg = "Resolve conflict (reduce for higher precedent production.)";
sln.action = reduce;
}
return sln;
}
lrGeneratorMixin.generate = function parser_generate (opt) {
opt = typal.mix.call({}, this.options, opt);
var code = "";
// check for illegal identifier
if (!opt.moduleName || !opt.moduleName.match(/^[A-Za-z_$][A-Za-z0-9_$]*$/)) {
opt.moduleName = "parser";
}
switch (opt.moduleType) {
case "js":
code = this.generateModule(opt);
break;
case "amd":
code = this.generateAMDModule(opt);
break;
default:
code = this.generateCommonJSModule(opt);
break;
}
return code;
};
lrGeneratorMixin.generateAMDModule = function generateAMDModule(opt){
opt = typal.mix.call({}, this.options, opt);
var module = this.generateModule_();
var out = '\n\ndefine(function(require){\n'
+ module.commonCode
+ '\nvar parser = '+ module.moduleCode
+ "\n"+this.moduleInclude
+ (this.lexer && this.lexer.generateModule ?
'\n' + this.lexer.generateModule() +
'\nparser.lexer = lexer;' : '')
+ '\nreturn parser;'
+ '\n});'
return out;
};
lrGeneratorMixin.generateCommonJSModule = function generateCommonJSModule (opt) {
opt = typal.mix.call({}, this.options, opt);
var moduleName = opt.moduleName || "parser";
var out = this.generateModule(opt)
+ "\n\n\nif (typeof require !== 'undefined' && typeof exports !== 'undefined') {"
+ "\nexports.parser = "+moduleName+";"
+ "\nexports.Parser = "+moduleName+".Parser;"
+ "\nexports.parse = function () { return "+moduleName+".parse.apply("+moduleName+", arguments); };"
+ "\n}";
return out;
};
lrGeneratorMixin.generateModule = function generateModule (opt) {
opt = typal.mix.call({}, this.options, opt);
var moduleName = opt.moduleName || "parser";
var out = "/* parser generated by jison-fork */\n";
out += (moduleName.match(/\./) ? moduleName : "var "+moduleName) +
" = " + this.generateModuleExpr();
return out;
};
lrGeneratorMixin.generateModuleExpr = function generateModuleExpr () {
var out = '';
var module = this.generateModule_();
out += "(function(){\n";
out += module.commonCode;
out += "\nvar parser = "+module.moduleCode;
out += "\n"+this.moduleInclude;
if (this.lexer && this.lexer.generateModule) {
out += this.lexer.generateModule();
out += "\nparser.lexer = lexer;";
}
out += "\nfunction Parser () {\n this.yy = {};\n}\n"
+ "Parser.prototype = parser;"
+ "parser.Parser = Parser;"
+ "\nreturn new Parser;\n})();";
return out;
};
function addTokenStack (fn) {
var parseFn = fn;
return fn;
}
// lex function that supports token stacks
function tokenStackLex() {
var token;
token = tstack.pop() || lexer.lex() || EOF;
// if token isn't its numeric value, convert
if (typeof token !== 'number') {
if (token instanceof Array) {
tstack = token;
token = tstack.pop();
}
token = self.symbols_[token] || token;
}
return token;
}
// Generates the code of the parser module, which consists of two parts:
// - module.commonCode: initialization code that should be placed before the module
// - module.moduleCode: code that creates the module object
lrGeneratorMixin.generateModule_ = function generateModule_ () {
var parseFn = String(parser.parse);
// if (!this.hasErrorRecovery) {
// parseFn = removeErrorRecovery(parseFn);
// }
// Generate code with fresh variable names
nextVariableId = 0;
var tableCode = this.generateTableCode(this.table);
// Generate the initialization code
var commonCode = tableCode.commonCode;
// Generate the module creation code
var moduleCode = "{";
moduleCode += [
"trace: " + String(this.trace || parser.trace),
"yy: {}",
"symbols_: " + JSON.stringify(this.symbols_),
"terminals_: " + JSON.stringify(this.terminals_).replace(/"([0-9]+)":/g,"$1:"),
"productions_: " + JSON.stringify(this.productions_),
"performAction: " + String(this.performAction),
"table: " + tableCode.moduleCode,
"defaultActions: " + JSON.stringify(this.defaultActions).replace(/"([0-9]+)":/g,"$1:"),
"parseError: " + String(this.parseError || (this.hasErrorRecovery ? traceParseError : parser.parseError)),
"parse: " + parseFn
].join(",\n");
moduleCode += "};";
return { commonCode: commonCode, moduleCode: moduleCode }
};
// Generate code that represents the specified parser table
lrGeneratorMixin.generateTableCode = function (table) {
var moduleCode = JSON.stringify(table);
var variables = [createObjectCode];
// Don't surround numerical property name numbers in quotes
moduleCode = moduleCode.replace(/"([0-9]+)"(?=:)/g, "$1");
// Replace objects with several identical values by function calls
// e.g., { 1: [6, 7]; 3: [6, 7], 4: [6, 7], 5: 8 } = o([1, 3, 4], [6, 7], { 5: 8 })
moduleCode = moduleCode.replace(/\{\d+:[^\}]+,\d+:[^\}]+\}/g, function (object) {
// Find the value that occurs with the highest number of keys
var value, frequentValue, key, keys = {}, keyCount, maxKeyCount = 0,
keyValue, keyValues = [], keyValueMatcher = /(\d+):([^:]+)(?=,\d+:|\})/g;
while ((keyValue = keyValueMatcher.exec(object))) {
// For each value, store the keys where that value occurs
key = keyValue[1];
value = keyValue[2];
keyCount = 1;
if (!(value in keys)) {
keys[value] = [key];
} else {
keyCount = keys[value].push(key);
}
// Remember this value if it is the most frequent one
if (keyCount > maxKeyCount) {
maxKeyCount = keyCount;
frequentValue = value;
}
}
// Construct the object with a function call if the most frequent value occurs multiple times
if (maxKeyCount > 1) {
// Collect all non-frequent values into a remainder object
for (value in keys) {
if (value !== frequentValue) {
for (var k = keys[value], i = 0, l = k.length; i < l; i++) {
keyValues.push(k[i] + ':' + value);
}
}
}
keyValues = keyValues.length ? ',{' + keyValues.join(',') + '}' : '';
// Create the function call `o(keys, value, remainder)`
object = 'o([' + keys[frequentValue].join(',') + '],' + frequentValue + keyValues + ')';
}
return object;
});
// Count occurrences of number lists
var list;
var lists = {};
var listMatcher = /\[[0-9,]+\]/g;
while (list = listMatcher.exec(moduleCode)) {
lists[list] = (lists[list] || 0) + 1;
}
// Replace frequently occurring number lists with variables
moduleCode = moduleCode.replace(listMatcher, function (list) {
var listId = lists[list];
// If listId is a number, it represents the list's occurrence frequency
if (typeof listId === 'number') {
// If the list does not occur frequently, represent it by the list
if (listId === 1) {
lists[list] = listId = list;
// If the list occurs frequently, represent it by a newly assigned variable
} else {
lists[list] = listId = createVariable();
variables.push(listId + '=' + list);
}
}
return listId;
});
// Return the variable initialization code and the table code
return {
commonCode: 'var ' + variables.join(',') + ';',
moduleCode: moduleCode
};
};
// Function that extends an object with the given value for all given keys
// e.g., o([1, 3, 4], [6, 7], { x: 1, y: 2 }) = { 1: [6, 7]; 3: [6, 7], 4: [6, 7], x: 1, y: 2 }
var createObjectCode = 'o=function(k,v,o,l){' +
'for(o=o||{},l=k.length;l--;o[k[l]]=v);' +
'return o}';
// Creates a variable with a unique name
function createVariable() {
var id = nextVariableId++;
var name = '$V';
do {
name += variableTokens[id % variableTokensLength];
id = ~~(id / variableTokensLength);
} while (id !== 0);
return name;
}
var nextVariableId = 0;
var variableTokens = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ_$';
var variableTokensLength = variableTokens.length;
// debug mixin for LR parser generators
function printAction (a, gen) {
var s = a[0] == 1 ? 'shift token (then go to state '+a[1]+')' :
a[0] == 2 ? 'reduce by rule: '+gen.productions[a[1]] :
'accept' ;
return s;
}
var lrGeneratorDebug = {
beforeparseTable: function () {
this.trace("Building parse table.");
},
afterparseTable: function () {
var self = this;
if (this.conflicts > 0) {
this.resolutions.forEach(function (r, i) {
if (r[2].bydefault) {
self.warn('Conflict at state: ',r[0], ', token: ',r[1], "\n ", printAction(r[2].r, self), "\n ", printAction(r[2].s, self));
}
});
this.trace("\n"+this.conflicts+" Conflict(s) found in grammar.");
}
this.trace("Done.");
},
aftercanonicalCollection: function (states) {
var trace = this.trace;
trace("\nItem sets\n------");
states.forEach(function (state, i) {
trace("\nitem set",i,"\n"+state.join("\n"), '\ntransitions -> ', JSON.stringify(state.edges));
});
}
};
var parser = typal.beget();
lrGeneratorMixin.createParser = function createParser () {
var p = eval(this.generateModuleExpr());
// for debugging
p.productions = this.productions;
var self = this;
function bind(method) {
return function() {
self.lexer = p.lexer;
return self[method].apply(self, arguments);
};
}
// backwards compatability
p.generate = bind('generate');
p.generateAMDModule = bind('generateAMDModule');
p.generateModule = bind('generateModule');
p.generateCommonJSModule = bind('generateCommonJSModule');
return p;
};
parser.trace = generator.trace;
parser.warn = generator.warn;
parser.error = generator.error;
function traceParseError (err, hash) {
this.trace(err);
}
function parseError (str, hash) {
if (hash.recoverable) {
this.trace(str);
} else {
throw new Error(str);
}
}
parser.parseError = lrGeneratorMixin.parseError = parseError;
parser.parse = function parse (input, script = null) {
// For Imba we are going to drop most of the features that are not used
// Locations are provided by the tokens from the lexer directly - so drop yylloc
// We dont really need the shared state (it seems)
var self = this,
stack = [0],
tstack = [], // token stack
vstack = [null], // semantic value stack
table = this.table,
yytext = '',
yylineno = 0,
yyleng = 0,
recovering = 0,
TERROR = 2,
EOF = 1;
// var args = lstack.slice.call(arguments, 1);
//this.reductionCount = this.shiftCount = 0;
var lexer = Object.create(this.lexer);
var yy = this.yy;
lexer.setInput(input,yy);
if (typeof yy.parseError === 'function') {
this.parseError = yy.parseError;
} else {
this.parseError = Object.getPrototypeOf(this).parseError; // what?
}
function popStack (n) {
stack.length = stack.length - 2 * n;
vstack.length = vstack.length - n;
}
var symbol, preErrorSymbol, state, action, a, r, yyval = {}, p, len, newState, expected;
function handleError(){
var error_rule_depth;
var errStr = '';
// Return the rule stack depth where the nearest error rule can be found.
// Return FALSE when no error recovery rule was found.
// we have no rules now
function locateNearestErrorRecoveryRule(state) {
var stack_probe = stack.length - 1;
var depth = 0;
// try to recover from error
for(;;) {
// check for error recovery rule in this state
if ((TERROR.toString()) in table[state]) {
return depth;
}
if (state === 0 || stack_probe < 2) {
return false; // No suitable error recovery rule available.
}
stack_probe -= 2; // popStack(1): [symbol, action]
state = stack[stack_probe];
++depth;
}
}
if (!recovering) {
// first see if there's any chance at hitting an error recovery rule:
error_rule_depth = locateNearestErrorRecoveryRule(state);
// Report error
expected = [];
var tsym = lexer.yytext;
var lastToken = tsym;
var tok = self.terminals_[symbol] || symbol;
// Find closest non-generated token
let tidx = lexer.tokens.indexOf(tsym);
let ttok = tsym;
while(ttok && ttok._loc == -1){
ttok = lexer.tokens[--tidx];
}
var tloc = ttok ? ttok._loc : -1;
var tend = tloc > -1 ? (tloc + (ttok._len || 0)) : -1;
var tpos = tloc != -1 ? "[" + ttok._loc + ":" + ttok._len + "]" : '[0:0]';
if (lexer.showPosition) {
errStr = 'Parse error at '+(tpos)+":\n"+lexer.showPosition()+"\nExpecting "+expected.join(', ') + ", got '" + (tok)+ "'";
} else {
// errStr = 'Parse error at '+(tpos)+": Unexpected " + (symbol == EOF ? "end of input" : ("'"+(tok)+"'"));
errStr = "Unexpected " + (symbol == EOF ? "end of input" : ("'"+(tok)+"'"));
}
if(script){
let err = script.addDiagnostic('error',{
message: errStr,
source: 'imba-parser',
range: script.rangeAt(tloc,tend)
})
err.raise();
}
self.parseError(errStr, {
lexer: lexer,
text: lexer.match,
token: tok,
offset: tloc,
length: (tend - tloc),
start: {offset: tloc},
end: {offset: tend},
line: lexer.yylineno,
expected: expected,
recoverable: (error_rule_depth !== false)
});
} else if (preErrorSymbol !== EOF) {
error_rule_depth = locateNearestErrorRecoveryRule(state);
}
// just recovered from another error
if (recovering == 3) {
if (symbol === EOF || preErrorSymbol === EOF) {
throw new Error(errStr || 'Parsing halted while starting to recover from another error.');
}
// discard current lookahead and grab another
yytext = lexer.yytext;
}
// try to recover from error
if (error_rule_depth === false) {
throw new Error(errStr || 'Parsing halted. No suitable error recovery rule available.');
}
popStack(error_rule_depth);
preErrorSymbol = (symbol == TERROR ? null : symbol); // save the lookahead token
symbol = TERROR; // insert generic error symbol as new lookahead
state = stack[stack.length-1];
action = table[state] && table[state][TERROR];
recovering = 3; // allow 3 real symbols to be shifted before reporting a new error
}
var __sym = this.symbols_;
var __prod = this.productions_;
while (true) {
// retreive state number from top of stack
state = stack[stack.length - 1];
if (symbol === null || typeof symbol == 'undefined') {
symbol = __sym[lexer.lex()] || EOF;
}
action = table[state] && table[state][symbol];
_handle_error:
if (typeof action === 'undefined' || !action.length || !action[0]) {
handleError();
}
switch (action[0]) {
case 1: // shift
stack.push(symbol);
stack.push(action[1]); // push state
vstack.push(lexer.yytext);
symbol = null;
if (!preErrorSymbol) { // normal execution/no error
yytext = lexer.yytext;
if (recovering > 0) {
recovering--;
}
} else {
// error just occurred, resume old lookahead f/ before error
symbol = preErrorSymbol;
preErrorSymbol = null;
}
break;
case 2:
len = __prod[action[1]][1];
// perform semantic action
yyval.$ = vstack[vstack.length-len];
r = this.performAction(yyval, yytext, yy, action[1], vstack);
if (typeof r !== 'undefined') {
return r;
}
while(len > 0) {
stack.pop();
stack.pop();
vstack.pop();
len--;
}
stack.push(__prod[action[1]][0]);
newState = table[stack[stack.length-2]][stack[stack.length-1]];
stack.push(newState);
vstack.push(yyval.$);
break;
case 3:
return true;
}
}
return true;
};
parser.init = function parser_init (dict) {
this.table = dict.table;
this.defaultActions = dict.defaultActions;
this.performAction = dict.performAction;
this.productions_ = dict.productions_;
this.symbols_ = dict.symbols_;
this.terminals_ = dict.terminals_;
};
/*
* LR(0) Parser
* */
var lr0 = generator.beget(lookaheadMixin, lrGeneratorMixin, {
type: "LR(0)",
afterconstructor: function lr0_afterconstructor () {
this.buildTable();
}
});
var LR0Generator = exports.LR0Generator = lr0.construct();
/*
* Simple LALR(1)
* */
var lalr = generator.beget(lookaheadMixin, lrGeneratorMixin, {
type: "LALR(1)",
afterconstructor: function (grammar, options) {
if (this.DEBUG) this.mix(lrGeneratorDebug, lalrGeneratorDebug); // mixin debug methods
options = options || {};
this.states = this.canonicalCollection();
this.terms_ = {};
var newg = this.newg = typal.beget(lookaheadMixin,{
oldg: this,
trace: this.trace,
nterms_: {},
DEBUG: false,
go_: function (r, B) {
r = r.split(":")[0]; // grab state #
B = B.map(function (b) { return b.slice(b.indexOf(":")+1); });
return this.oldg.go(r, B);
}
});
newg.nonterminals = {};
newg.productions = [];
this.inadequateStates = [];
// if true, only lookaheads in inadequate states are computed (faster, larger table)
// if false, lookaheads for all reductions will be computed (slower, smaller table)
this.onDemandLookahead = options.onDemandLookahead || false;
this.buildNewGrammar();
newg.computeLookaheads();
this.unionLookaheads();
this.table = this.parseTable(this.states);
this.defaultActions = findDefaults(this.table);
},
lookAheads: function LALR_lookaheads (state, item) {
return (!!this.onDemandLookahead && !state.inadequate) ? this.terminals : item.follows;
},
go: function LALR_go (p, w) {
var q = parseInt(p, 10);
for (var i=0;i<w.length;i++) {
q = this.states.item(q).edges[w[i]] || q;
}
return q;
},
goPath: function LALR_goPath (p, w) {
var q = parseInt(p, 10),t,
path = [];
for (var i=0;i<w.length;i++) {
t = w[i] ? q+":"+w[i] : '';
if (t) this.newg.nterms_[t] = q;
path.push(t);
q = this.states.item(q).edges[w[i]] || q;
this.terms_[t] = w[i];
}
return {path: path, endState: q};
},
// every disjoint reduction of a nonterminal becomes a produciton in G'
buildNewGrammar: function LALR_buildNewGrammar () {
var self = this,
newg = this.newg;
this.states.forEach(function (state, i) {
state.forEach(function (item) {
if (item.dotPosition === 0) {
// new symbols are a combination of state and transition symbol
var symbol = i+":"+item.production.symbol;
self.terms_[symbol] = item.production.symbol;
newg.nterms_[symbol] = i;
if (!newg.nonterminals[symbol])
newg.nonterminals[symbol] = new Nonterminal(symbol);
var pathInfo = self.goPath(i, item.production.handle);
var p = new Production(symbol, pathInfo.path, newg.productions.length);
newg.productions.push(p);
newg.nonterminals[symbol].productions.push(p);
// store the transition that get's 'backed up to' after reduction on path
var handle = item.production.handle.join(' ');
var goes = self.states.item(pathInfo.endState).goes;
if (!goes[handle])
goes[handle] = [];
goes[handle].push(symbol);
//self.trace('new production:',p);
}
});
if (state.inadequate)
self.inadequateStates.push(i);
});
},
unionLookaheads: function LALR_unionLookaheads () {
var self = this,
newg = this.newg,
states = !!this.onDemandLookahead ? this.inadequateStates : this.states;
states.forEach(function union_states_forEach (i) {
var state = typeof i === 'number' ? self.states.item(i) : i,
follows = [];
if (state.reductions.length)
state.reductions.forEach(function union_reduction_forEach (item) {
var follows = {};
for (var k=0;k<item.follows.length;k++) {
follows[item.follows[k]] = true;
}
state.goes[item.production.handle.join(' ')].forEach(function reduction_goes_forEach (symbol) {
newg.nonterminals[symbol].follows.forEach(function goes_follows_forEach (symbol) {
var terminal = self.terms_[symbol];
if (!follows[terminal]) {
follows[terminal]=true;
item.follows.push(terminal);
}
});
});
//self.trace('unioned item', item);
});
});
}
});
var LALRGenerator = exports.LALRGenerator = lalr.construct();
// LALR generator debug mixin
var lalrGeneratorDebug = {
trace: function trace () {
Jison.print.apply(null, arguments);
},
beforebuildNewGrammar: function () {
this.trace(this.states.size()+" states.");
this.trace("Building lookahead grammar.");
},
beforeunionLookaheads: function () {
this.trace("Computing lookaheads.");
}
};
/*
* Lookahead parser definitions
*
* Define base type
* */
var lrLookaheadGenerator = generator.beget(lookaheadMixin, lrGeneratorMixin, {
afterconstructor: function lr_aftercontructor () {
this.computeLookaheads();
this.buildTable();
}
});
/*
* SLR Parser
* */
var SLRGenerator = exports.SLRGenerator = lrLookaheadGenerator.construct({
type: "SLR(1)",
lookAheads: function SLR_lookAhead (state, item) {
return this.nonterminals[item.production.symbol].follows;
}
});
/*
* LR(1) Parser
* */
var lr1 = lrLookaheadGenerator.beget({
type: "Canonical LR(1)",
lookAheads: function LR_lookAheads (state, item) {
return item.follows;
},
Item: lrGeneratorMixin.Item.prototype.construct({
afterconstructor: function () {
this.id = this.production.id+'a'+this.dotPosition+'a'+this.follows.sort().join(',');
},
eq: function (e) {
return e.id === this.id;
}
}),
closureOperation: function LR_ClosureOperation (itemSet /*, closureSet*/) {
var closureSet = new this.ItemSet();
var self = this;
var set = itemSet,
itemQueue, syms = {};
do {
itemQueue = new Set();
closureSet.concat(set);
set.forEach(function (item) {
var symbol = item.markedSymbol;
var b, r;
// if token is a nonterminal, recursively add closures
if (symbol && self.nonterminals[symbol]) {
r = item.remainingHandle();
b = self.first(item.remainingHandle());
if (b.length === 0 || item.production.nullable || self.nullable(r)) {
b = b.concat(item.follows);
}
self.nonterminals[symbol].productions.forEach(function (production) {
var newItem = new self.Item(production, 0, b);
if(!closureSet.contains(newItem) && !itemQueue.contains(newItem)) {
itemQueue.push(newItem);
}
});
} else if (!symbol) {
// reduction
closureSet.reductions.push(item);
}
});
set = itemQueue;
} while (!itemQueue.isEmpty());
return closureSet;
}
});
var LR1Generator = exports.LR1Generator = lr1.construct();
/*
* LL Parser
* */
var ll = generator.beget(lookaheadMixin, {
type: "LL(1)",
afterconstructor: function ll_aftercontructor () {
this.computeLookaheads();
this.table = this.parseTable(this.productions);
},
parseTable: function llParseTable (productions) {
var table = {},
self = this;
productions.forEach(function (production, i) {
var row = table[production.symbol] || {};
var tokens = production.first;
if (self.nullable(production.handle)) {
Set.union(tokens, self.nonterminals[production.symbol].follows);
}
tokens.forEach(function (token) {
if (row[token]) {
row[token].push(i);
self.conflicts++;
} else {
row[token] = [i];
}
});
table[production.symbol] = row;
});
return table;
}
});
var LLGenerator = exports.LLGenerator = ll.construct();
Jison.Generator = function Jison_Generator (g, options) {
var opt = typal.mix.call({}, g.options, options);
switch (opt.type) {
case 'lr0':
return new LR0Generator(g, opt);
case 'slr':
return new SLRGenerator(g, opt);
case 'lr':
return new LR1Generator(g, opt);
case 'll':
return new LLGenerator(g, opt);
default:
return new LALRGenerator(g, opt);
}
};
return function Parser (g, options) {
var gen = Jison.Generator(g, options);
return gen.createParser();
};
})();