iter.js

Ajax下日志框架

/***

MochiKit.Iter 1.3.1

See <http://mochikit.com/> for documentation, downloads, license, etc.

(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 = "1.3.1";
MochiKit.Base.update(MochiKit.Iter, {
    __repr__: function () {
        return "[" + this.NAME + " " + this.VERSION + "]";
    },
    toString: function () {
        return this.__repr__();
    },

    registerIteratorFactory: function (name, check, iterfactory, /* optional */ override) {
        MochiKit.Iter.iteratorRegistry.register(name, check, iterfactory, override);
    },

    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();
        }
        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;
        }
    },

    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)
        };
    },

    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();
                }
            }
        };
    },

    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;
            }
        };
    },
            
    next: function (iterator) {
        return iterator.next();
    },

    izip: function (p, q/*, ...*/) {
        var m = MochiKit.Base;
        var next = MochiKit.Iter.next;
        var iterables = m.map(iter, arguments);
        return {
            repr: function () { return "izip(...)"; },
            toString: m.forwardCall("repr"),
            next: function () { return m.map(next, iterables); }
        };
    },

    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;
            }
        };
    },

    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;
            }
        };
    },
     
    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;
            }
        };
    },

    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));
            }
        };
    },
        
    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());
            }
        };
    },

    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;
            }
        };
    },

    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;
            }
        };
    },

    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;
            }
        };
    },

    tee: function (iterable, n/* = 2 */) {
        var rval = [];
        var sync = {
            "pos": [],
            "deque": [],
            "max": -1,
            "min": -1
        };
        if (arguments.length == 1) {
            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;
    },

    list: function (iterable) {
        // Fast-path for Array and Array-like
        var m = MochiKit.Base;
        if (typeof(iterable.slice) == 'function') {
            return iterable.slice();
        } else if (m.isArrayLike(iterable)) {
            return m.concat(iterable);
        }