// Set class to wrap arrays
var typal = require("@runkit/jison/typal/1.0.1");
var setMixin = {
constructor: function Set_constructor (set, raw) {
this._items = [];
if (set && set.constructor === Array)
this._items = raw ? set: set.slice(0);
else if(arguments.length)
this._items = [].slice.call(arguments,0);
},
concat: function concat (setB) {
this._items.push.apply(this._items, setB._items || setB);
return this;
},
eq: function eq (set) {
return this._items.length === set._items.length && this.subset(set);
},
indexOf: function indexOf (item) {
if(item && item.eq) {
for(var k=0; k<this._items.length;k++)
if(item.eq(this._items[k]))
return k;
return -1;
}
return this._items.indexOf(item);
},
union: function union (set) {
return (new Set(this._items)).concat(this.complement(set));
},
intersection: function intersection (set) {
return this.filter(function (elm) {
return set.contains(elm);
});
},
complement: function complement (set) {
var that = this;
return set.filter(function sub_complement (elm) {
return !that.contains(elm);
});
},
subset: function subset (set) {
var cont = true;
for (var i=0; i<this._items.length && cont;i++) {
cont = cont && set.contains(this._items[i]);
}
return cont;
},
superset: function superset (set) {
return set.subset(this);
},
joinSet: function joinSet (set) {
return this.concat(this.complement(set));
},
contains: function contains (item) { return this.indexOf(item) !== -1; },
item: function item (v, val) { return this._items[v]; },
i: function i (v, val) { return this._items[v]; },
first: function first () { return this._items[0]; },
last: function last () { return this._items[this._items.length-1]; },
size: function size () { return this._items.length; },
isEmpty: function isEmpty () { return this._items.length === 0; },
copy: function copy () { return new Set(this._items); },
toString: function toString () { return this._items.toString(); }
};
"push shift unshift forEach some every join sort".split(' ').forEach(function (e,i) {
setMixin[e] = function () { return Array.prototype[e].apply(this._items, arguments); };
setMixin[e].name = e;
});
"filter slice map".split(' ').forEach(function (e,i) {
setMixin[e] = function () { return new Set(Array.prototype[e].apply(this._items, arguments), true); };
setMixin[e].name = e;
});
var Set = typal.construct(setMixin).mix({
union: function (a, b) {
var ar = {};
for (var k=a.length-1;k >=0;--k) {
ar[a[k]] = true;
}
for (var i=b.length-1;i >= 0;--i) {
if (!ar[b[i]]) {
a.push(b[i]);
}
}
return a;
}
});
module.exports.Set = Set;
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