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import Enumerable from '../linq.js'
/////////////////////////////// Simple Lambda Expressions
console.log('# Simple Lambda Expressions\n');
// Anonymous functionEnumerable.range(1, 3).select(function(value, index) { return index + ':' + value }).log().toJoinedString();
// Arrow function syntaxEnumerable.range(1, 3).select((value, index) => index + ':' + value).log().toJoinedString();
// Lambdas can also be passed as stringsEnumerable.range(1, 3).select("(value, index) => index + '/' + value").log().toJoinedString();
// If the number of arguments is one, we can use default iterator variable '$'Enumerable.range(1, 3).select("$*2").log().toJoinedString(); // same as i => i * 2
// "" is a shortcut for "x => x" (identity function)Enumerable.range(4, 7).join(Enumerable.range(8, 5), "", "", (outer, inner) => outer * inner).log().toJoinedString();

///////////////////////////////// Scope of lambda expressions
console.log('\n# Scope of lambda expressions\n');
// lambda expressions cannot access the closure when the string syntax is usedtry {  var number = 3;  Enumerable.range(1,10).where("$ == number").log().toJoinedString();} catch (e) {  console.log("can't find number");}
// use anonymous function to capture variableEnumerable.range(1,10).where(function(i){return i == number}).log().toJoinedString();

/////////////////////////////// Initializing from objects
console.log('\n# Initializing from objects\n');
var object = {foo:"a", "bar":100, "foobar":true};Enumerable.from(object).forEach(function(obj) { console.log(obj.key + ":" + obj.value) });

/////////////////////////////////////// Continue and break when iterating
console.log('\n# Continue and break when iterating\n');
Enumerable.repeat("foo", 10).forEach(function(value, index){    if (index % 2 == 0) return; // continue    if (index > 6) return false; // break    console.log(index + ":" + value);});

//////////////////////////////////// Grouping and ref/value compare
console.log('\n# Grouping and ref/value compare\n');
// ref compareconsole.log((new Date(2000, 1, 1) == new Date(2000, 1, 1))); // falseconsole.log(({ a: 0} == { a: 0 })); // false
console.log("------");var objects = [    { Date: new Date(2000, 1, 1), Id: 1 },    { Date: new Date(2010, 5, 5), Id: 2 },    { Date: new Date(2000, 1, 1), Id: 3 }]
// ref compare, cannot do groupingEnumerable.from(objects)    .groupBy("$.Date", "$.Id",        function (key, group) { return { date: key, ids: group.toJoinedString(',')} })    .log("$.date + ':' + $.ids").toJoinedString();
console.log("------");
// use fourth argument to groupBy (compareSelector)Enumerable.from(objects)    .groupBy("$.Date", "$.Id",        function (key, group) { return { date: key, ids: group.toJoinedString(',')} },        function (key) { return key.toString() })    .log("$.date + ':' + $.ids").toJoinedString();

//////////////////////////////// Regular Expression matches
console.log('\n# Regular Expression matches\n');
// Enumerable.matches return Enumerable<MatchObject>
var input = "abcdefgABzDefabgdg";Enumerable.matches(input, "ab(.)d", "i").forEach(function(match){    for (var prop in match)    {        console.log(prop + " : " + match[prop]);    }    console.log("toString() : " + match.toString());    console.log("---");});

///////////////////////////////////// LazyEvaluation and InfinityList
console.log('\n# LazyEvaluation and InfinityList\n');
// first radius of a circle with area over 10000var result = Enumerable.toInfinity(1).where(r => r * r * Math.PI > 10000).first();console.log(result);

//////////////// Dictionary
console.log('\n# Dictionary\n');
// sample classvar cls = function (a, b){    this.a = a;    this.b = b;}var instanceA = new cls("a", 100);var instanceB = new cls("b", 2000);
// create blank dictionaryvar dict = Enumerable.empty().toDictionary();// create blank dictionary (using compareSelector)var dict = Enumerable.empty().toDictionary("","",function (x) { return x.a + x.b });
dict.add(instanceA, "zzz");dict.add(instanceB, "huga");console.log(dict.get(instanceA)); // zzzconsole.log(dict.get(instanceB)); // huga
// enumerable (to keyvaluePair)dict.toEnumerable().forEach(function (kvp){    console.log(kvp.key.a + ":" + kvp.value);});

/////////////////////////////// Nondeterministic Programs
console.log('\n# Nondeterministic programs\n');
// a puzzle from Structure and Interpretation of Computer Programs// http://sarabander.github.io/sicp/html/4_002e3.xhtml
var apart = Enumerable.range(1, 5);var answers = apart    .selectMany(function(baker){ return apart    .selectMany(function(cooper){ return apart    .selectMany(function(fletcher){ return apart    .selectMany(function(miller){ return apart    .select(function(smith){ return {        baker: baker, cooper: cooper, fletcher: fletcher, miller: miller, smith: smith}})})})})})    .where(function(x){ return Enumerable.from(x).distinct("$.value").count() == 5 })    .where("$.baker != 5")    .where("$.cooper != 1")    .where("$.fletcher != 1 && $.fletcher != 5")    .where("$.miller > $.cooper")    .where("Math.abs($.smith - $.fletcher) != 1")    .where("Math.abs($.fletcher - $.cooper) != 1");
answers.selectMany("").log("$.key + ':' + $.value").toJoinedString();