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/***
MochiKit.Iter 1.4
(c) 2005 Bob Ippolito. All rights Reserved.
***/
if (typeof(dojo) != 'undefined') {
dojo.provide('MochiKit.Iter');
dojo.require('MochiKit.Base');
}
if (typeof(JSAN) != 'undefined') {
JSAN.use("MochiKit.Base", []);
}
try {
if (typeof(MochiKit.Base) == 'undefined') {
throw "";
}
} catch (e) {
throw "MochiKit.Iter depends on MochiKit.Base!";
}
if (typeof(MochiKit.Iter) == 'undefined') {
MochiKit.Iter = {};
}
MochiKit.Iter.NAME = "MochiKit.Iter";
MochiKit.Iter.VERSION = "1.4";
MochiKit.Base.update(MochiKit.Iter, {
__repr__: function () {
return "[" + this.NAME + " " + this.VERSION + "]";
},
toString: function () {
return this.__repr__();
},
/** @id MochiKit.Iter.registerIteratorFactory */
registerIteratorFactory: function (name, check, iterfactory, /* optional */ override) {
MochiKit.Iter.iteratorRegistry.register(name, check, iterfactory, override);
},
/** @id MochiKit.Iter.iter */
iter: function (iterable, /* optional */ sentinel) {
var self = MochiKit.Iter;
if (arguments.length == 2) {
return self.takewhile(
function (a) { return a != sentinel; },
iterable
);
}
if (typeof(iterable.next) == 'function') {
return iterable;
} else if (typeof(iterable.iter) == 'function') {
return iterable.iter();
/*
} else if (typeof(iterable.__iterator__) == 'function') {
//
// XXX: We can't support JavaScript 1.7 __iterator__ directly
// because of Object.prototype.__iterator__
//
return iterable.__iterator__();
*/
}
try {
return self.iteratorRegistry.match(iterable);
} catch (e) {
var m = MochiKit.Base;
if (e == m.NotFound) {
e = new TypeError(typeof(iterable) + ": " + m.repr(iterable) + " is not iterable");
}
throw e;
}
},
/** @id MochiKit.Iter.count */
count: function (n) {
if (!n) {
n = 0;
}
var m = MochiKit.Base;
return {
repr: function () { return "count(" + n + ")"; },
toString: m.forwardCall("repr"),
next: m.counter(n)
};
},
/** @id MochiKit.Iter.cycle */
cycle: function (p) {
var self = MochiKit.Iter;
var m = MochiKit.Base;
var lst = [];
var iterator = self.iter(p);
return {
repr: function () { return "cycle(...)"; },
toString: m.forwardCall("repr"),
next: function () {
try {
var rval = iterator.next();
lst.push(rval);
return rval;
} catch (e) {
if (e != self.StopIteration) {
throw e;
}
if (lst.length === 0) {
this.next = function () {
throw self.StopIteration;
};
} else {
var i = -1;
this.next = function () {
i = (i + 1) % lst.length;
return lst[i];
};
}
return this.next();
}
}
};
},
/** @id MochiKit.Iter.repeat */
repeat: function (elem, /* optional */n) {
var m = MochiKit.Base;
if (typeof(n) == 'undefined') {
return {
repr: function () {
return "repeat(" + m.repr(elem) + ")";
},
toString: m.forwardCall("repr"),
next: function () {
return elem;
}
};
}
return {
repr: function () {
return "repeat(" + m.repr(elem) + ", " + n + ")";
},
toString: m.forwardCall("repr"),
next: function () {
if (n <= 0) {
throw MochiKit.Iter.StopIteration;
}
n -= 1;
return elem;
}
};
},
/** @id MochiKit.Iter.next */
next: function (iterator) {
return iterator.next();
},
/** @id MochiKit.Iter.izip */
izip: function (p, q/*, ...*/) {
var m = MochiKit.Base;
var self = MochiKit.Iter;
var next = self.next;
var iterables = m.map(self.iter, arguments);
return {
repr: function () { return "izip(...)"; },
toString: m.forwardCall("repr"),
next: function () { return m.map(next, iterables); }
};
},
/** @id MochiKit.Iter.ifilter */
ifilter: function (pred, seq) {
var m = MochiKit.Base;
seq = MochiKit.Iter.iter(seq);
if (pred === null) {
pred = m.operator.truth;
}
return {
repr: function () { return "ifilter(...)"; },
toString: m.forwardCall("repr"),
next: function () {
while (true) {
var rval = seq.next();
if (pred(rval)) {
return rval;
}
}
// mozilla warnings aren't too bright
return undefined;
}
};
},
/** @id MochiKit.Iter.ifilterfalse */
ifilterfalse: function (pred, seq) {
var m = MochiKit.Base;
seq = MochiKit.Iter.iter(seq);
if (pred === null) {
pred = m.operator.truth;
}
return {
repr: function () { return "ifilterfalse(...)"; },
toString: m.forwardCall("repr"),
next: function () {
while (true) {
var rval = seq.next();
if (!pred(rval)) {
return rval;
}
}
// mozilla warnings aren't too bright
return undefined;
}
};
},
/** @id MochiKit.Iter.islice */
islice: function (seq/*, [start,] stop[, step] */) {
var self = MochiKit.Iter;
var m = MochiKit.Base;
seq = self.iter(seq);
var start = 0;
var stop = 0;
var step = 1;
var i = -1;
if (arguments.length == 2) {
stop = arguments[1];
} else if (arguments.length == 3) {
start = arguments[1];
stop = arguments[2];
} else {
start = arguments[1];
stop = arguments[2];
step = arguments[3];
}
return {
repr: function () {
return "islice(" + ["...", start, stop, step].join(", ") + ")";
},
toString: m.forwardCall("repr"),
next: function () {
var rval;
while (i < start) {
rval = seq.next();
i++;
}
if (start >= stop) {
throw self.StopIteration;
}
start += step;
return rval;
}
};
},
/** @id MochiKit.Iter.imap */
imap: function (fun, p, q/*, ...*/) {
var m = MochiKit.Base;
var self = MochiKit.Iter;
var iterables = m.map(self.iter, m.extend(null, arguments, 1));
var map = m.map;
var next = self.next;
return {
repr: function () { return "imap(...)"; },
toString: m.forwardCall("repr"),
next: function () {
return fun.apply(this, map(next, iterables));
}
};
},
/** @id MochiKit.Iter.applymap */
applymap: function (fun, seq, self) {
seq = MochiKit.Iter.iter(seq);
var m = MochiKit.Base;
return {
repr: function () { return "applymap(...)"; },
toString: m.forwardCall("repr"),
next: function () {
return fun.apply(self, seq.next());
}
};
},
/** @id MochiKit.Iter.chain */
chain: function (p, q/*, ...*/) {
// dumb fast path
var self = MochiKit.Iter;
var m = MochiKit.Base;
if (arguments.length == 1) {
return self.iter(arguments[0]);
}
var argiter = m.map(self.iter, arguments);
return {
repr: function () { return "chain(...)"; },
toString: m.forwardCall("repr"),
next: function () {
while (argiter.length > 1) {
try {
return argiter[0].next();
} catch (e) {
if (e != self.StopIteration) {
throw e;
}
argiter.shift();
}
}
if (argiter.length == 1) {
// optimize last element
var arg = argiter.shift();
this.next = m.bind("next", arg);
return this.next();
}
throw self.StopIteration;
}
};
},
/** @id MochiKit.Iter.takewhile */
takewhile: function (pred, seq) {
var self = MochiKit.Iter;
seq = self.iter(seq);
return {
repr: function () { return "takewhile(...)"; },
toString: MochiKit.Base.forwardCall("repr"),
next: function () {
var rval = seq.next();
if (!pred(rval)) {
this.next = function () {
throw self.StopIteration;
};
this.next();
}
return rval;
}
};
},
/** @id MochiKit.Iter.dropwhile */
dropwhile: function (pred, seq) {
seq = MochiKit.Iter.iter(seq);
var m = MochiKit.Base;
var bind = m.bind;
return {
"repr": function () { return "dropwhile(...)"; },
"toString": m.forwardCall("repr"),
"next": function () {
while (true) {
var rval = seq.next();
if (!pred(rval)) {
break;
}
}
this.next = bind("next", seq);
return rval;
}
};
},
_tee: function (ident, sync, iterable) {
sync.pos[ident] = -1;
var m = MochiKit.Base;
var listMin = m.listMin;
return {
repr: function () { return "tee(" + ident + ", ...)"; },
toString: m.forwardCall("repr"),
next: function () {
var rval;
var i = sync.pos[ident];
if (i == sync.max) {
rval = iterable.next();
sync.deque.push(rval);
sync.max += 1;
sync.pos[ident] += 1;
} else {
rval = sync.deque[i - sync.min];
sync.pos[ident] += 1;
if (i == sync.min && listMin(sync.pos) != sync.min) {
sync.min += 1;
sync.deque.shift();
}
}
return rval;
}
};
},
/** @id MochiKit.Iter.tee */
tee: function (iterable, n/* = 2 */) {
var rval = [];
var sync = {
"pos": [],
"deque": [],
"max": -1,
"min": -1
};
if (arguments.length == 1 || typeof(n) == "undefined" || n === null) {
n = 2;
}
var self = MochiKit.Iter;
iterable = self.iter(iterable);
var _tee = self._tee;
for (var i = 0; i < n; i++) {
rval.push(_tee(i, sync, iterable));
}
return rval;
},
/** @id MochiKit.Iter.list */
list: function (iterable) {
// Fast-path for Array and Array-like
var rval;
if (iterable instanceof Array) {
return iterable.slice();
}
// this is necessary to avoid a Safari crash
if (typeof(iterable) == "function" &&
!(iterable instanceof Function) &&
typeof(iterable.length) == 'number') {
rval = [];
for (var i = 0; i < iterable.length; i++) {
rval.push(iterable[i]);
}
return rval;
}
var self = MochiKit.Iter;
iterable = self.iter(iterable);
var rval = [];
try {
while (true) {
rval.push(iterable.next());
}
} catch (e) {
if (e != self.StopIteration) {
throw e;
}
return rval;
}
// mozilla warnings aren't too bright
return undefined;
},
/** @id MochiKit.Iter.reduce */
reduce: function (fn, iterable, /* optional */initial) {
var i = 0;
var x = initial;
var self = MochiKit.Iter;
iterable = self.iter(iterable);
if (arguments.length < 3) {
try {
x = iterable.next();
} catch (e) {
if (e == self.StopIteration) {
e = new TypeError("reduce() of empty sequence with no initial value");
}
throw e;
}
i++;
}
try {
while (true) {
x = fn(x, iterable.next());
}
} catch (e) {
if (e != self.StopIteration) {
throw e;
}
}
return x;
},
/** @id MochiKit.Iter.range */
range: function (/* [start,] stop[, step] */) {
var start = 0;
var stop = 0;
var step = 1;
if (arguments.length == 1) {
stop = arguments[0];
} else if (arguments.length == 2) {
start = arguments[0];
stop = arguments[1];
} else if (arguments.length == 3) {
start = arguments[0];
stop = arguments[1];
step = arguments[2];
} else {
throw new TypeError("range() takes 1, 2, or 3 arguments!");
}
if (step === 0) {
throw new TypeError("range() step must not be 0");
}
return {
next: function () {
if ((step > 0 && start >= stop) || (step < 0 && start <= stop)) {
throw MochiKit.Iter.StopIteration;
}
var rval = start;
start += step;
return rval;
},
repr: function () {
return "range(" + [start, stop, step].join(", ") + ")";
},
toString: MochiKit.Base.forwardCall("repr")
};
},
/** @id MochiKit.Iter.sum */
sum: function (iterable, start/* = 0 */) {
if (typeof(start) == "undefined" || start === null) {
start = 0;
}
var x = start;
var self = MochiKit.Iter;
iterable = self.iter(iterable);
try {
while (true) {
x += iterable.next();
}
} catch (e) {
if (e != self.StopIteration) {
throw e;
}
}
return x;
},
/** @id MochiKit.Iter.exhaust */
exhaust: function (iterable) {
var self = MochiKit.Iter;
iterable = self.iter(iterable);
try {
while (true) {
iterable.next();
}
} catch (e) {
if (e != self.StopIteration) {
throw e;
}
}
},
/** @id MochiKit.Iter.forEach */
forEach: function (iterable, func, /* optional */self) {
var m = MochiKit.Base;
if (arguments.length > 2) {
func = m.bind(func, self);
}
// fast path for array
if (m.isArrayLike(iterable)) {
try {
for (var i = 0; i < iterable.length; i++) {
func(iterable[i]);
}
} catch (e) {
if (e != MochiKit.Iter.StopIteration) {
throw e;
}
}
} else {
self = MochiKit.Iter;
self.exhaust(self.imap(func, iterable));
}
},
/** @id MochiKit.Iter.every */
every: function (iterable, func) {
var self = MochiKit.Iter;
try {
self.ifilterfalse(func, iterable).next();
return false;
} catch (e) {
if (e != self.StopIteration) {
throw e;
}
return true;
}
},
/** @id MochiKit.Iter.sorted */
sorted: function (iterable, /* optional */cmp) {
var rval = MochiKit.Iter.list(iterable);
if (arguments.length == 1) {
cmp = MochiKit.Base.compare;
}
rval.sort(cmp);
return rval;
},
/** @id MochiKit.Iter.reversed */
reversed: function (iterable) {
var rval = MochiKit.Iter.list(iterable);
rval.reverse();
return rval;
},
/** @id MochiKit.Iter.some */
some: function (iterable, func) {
var self = MochiKit.Iter;
try {
self.ifilter(func, iterable).next();
return true;
} catch (e) {
if (e != self.StopIteration) {
throw e;
}
return false;
}
},
/** @id MochiKit.Iter.iextend */
iextend: function (lst, iterable) {
if (MochiKit.Base.isArrayLike(iterable)) {
// fast-path for array-like
for (var i = 0; i < iterable.length; i++) {
lst.push(iterable[i]);
}
} else {
var self = MochiKit.Iter;
iterable = self.iter(iterable);
try {
while (true) {
lst.push(iterable.next());
}
} catch (e) {
if (e != self.StopIteration) {
throw e;
}
}
}
return lst;
},
/** @id MochiKit.Iter.groupby */
groupby: function(iterable, /* optional */ keyfunc) {
var m = MochiKit.Base;
var self = MochiKit.Iter;
if (arguments.length < 2) {
keyfunc = m.operator.identity;
}
iterable = self.iter(iterable);
// shared
var pk = undefined;
var k = undefined;
var v;
function fetch() {
v = iterable.next();
k = keyfunc(v);
};
function eat() {
var ret = v;
v = undefined;
return ret;
};
var first = true;
var compare = m.compare;
return {
repr: function () { return "groupby(...)"; },
next: function() {
// iterator-next
// iterate until meet next group
while (compare(k, pk) === 0) {
fetch();
if (first) {
first = false;
break;
}
}
pk = k;
return [k, {
next: function() {
// subiterator-next
if (v == undefined) { // Is there something to eat?
fetch();
}
if (compare(k, pk) !== 0) {
throw self.StopIteration;
}
return eat();
}
}];
}
};
},
/** @id MochiKit.Iter.groupby_as_array */
groupby_as_array: function (iterable, /* optional */ keyfunc) {
var m = MochiKit.Base;
var self = MochiKit.Iter;
if (arguments.length < 2) {
keyfunc = m.operator.identity;
}
iterable = self.iter(iterable);
var result = [];
var first = true;
var prev_key;
var compare = m.compare;
while (true) {
try {
var value = iterable.next();
var key = keyfunc(value);
} catch (e) {
if (e == self.StopIteration) {
break;
}
throw e;
}
if (first || compare(key, prev_key) !== 0) {
var values = [];
result.push([key, values]);
}
values.push(value);
first = false;
prev_key = key;
}
return result;
},
/** @id MochiKit.Iter.arrayLikeIter */
arrayLikeIter: function (iterable) {
var i = 0;
return {
repr: function () { return "arrayLikeIter(...)"; },
toString: MochiKit.Base.forwardCall("repr"),
next: function () {
if (i >= iterable.length) {
throw MochiKit.Iter.StopIteration;
}
return iterable[i++];
}
};
},
/** @id MochiKit.Iter.hasIterateNext */
hasIterateNext: function (iterable) {
return (iterable && typeof(iterable.iterateNext) == "function");
},
/** @id MochiKit.Iter.iterateNextIter */
iterateNextIter: function (iterable) {
return {
repr: function () { return "iterateNextIter(...)"; },
toString: MochiKit.Base.forwardCall("repr"),
next: function () {
var rval = iterable.iterateNext();
if (rval === null || rval === undefined) {
throw MochiKit.Iter.StopIteration;
}
return rval;
}
};
}
});
MochiKit.Iter.EXPORT_OK = [
"iteratorRegistry",
"arrayLikeIter",
"hasIterateNext",
"iterateNextIter",
];
MochiKit.Iter.EXPORT = [
"StopIteration",
"registerIteratorFactory",
"iter",
"count",
"cycle",
"repeat",
"next",
"izip",
"ifilter",
"ifilterfalse",
"islice",
"imap",
"applymap",
"chain",
"takewhile",
"dropwhile",
"tee",
"list",
"reduce",
"range",
"sum",
"exhaust",
"forEach",
"every",
"sorted",
"reversed",
"some",
"iextend",
"groupby",
"groupby_as_array"
];
MochiKit.Iter.__new__ = function () {
var m = MochiKit.Base;
// Re-use StopIteration if exists (e.g. SpiderMonkey)
if (typeof(StopIteration) != "undefined") {
this.StopIteration = StopIteration;
} else {
/** @id MochiKit.Iter.StopIteration */
this.StopIteration = new m.NamedError("StopIteration");
}
this.iteratorRegistry = new m.AdapterRegistry();
// Register the iterator factory for arrays
this.registerIteratorFactory(
"arrayLike",
m.isArrayLike,
this.arrayLikeIter
);
this.registerIteratorFactory(
"iterateNext",
this.hasIterateNext,
this.iterateNextIter
);
this.EXPORT_TAGS = {
":common": this.EXPORT,
":all": m.concat(this.EXPORT, this.EXPORT_OK)
};
m.nameFunctions(this);
};
MochiKit.Iter.__new__();
//
// XXX: Internet Explorer blows
//
if (MochiKit.__export__) {
reduce = MochiKit.Iter.reduce;
}
MochiKit.Base._exportSymbols(this, MochiKit.Iter);