groovelab/0_雛形.js

## 0_雛形.js
<!doctype html>
<html>
<head>
<meta charset="utf8">
<title>JavaScriptで学ぶ関数型プログラミング テストページ</title>
</head>
<body>
<h1>JavaScriptで学ぶ関数型プログラミングのテストページ</h1>
<script type="text/javascript" src="http://underscorejs.org/underscore.js"></script>
<script type="text/javascript">

//  ここにコードを記述する

</script>
</body>
</html>

## 1_命令型プログラミング.js
var ret = [];
for (var i=0; i<10; i++) {
    var result = i * i;
    ret.push(result);
}
console.log(ret);   // [0, 1, 4, 9, 16, 25, 36, 49, 64, 81]

## 2_関数型プログラミング.js
var squareUntil = function(limit) {
    return _.map(_.range(limit), function(n) {
        return n * n;
    });
}
console.log(squareUntil(10)); // [0, 1, 4, 9, 16, 25, 36, 49, 64, 81]

## 3_currying.js
function curry2(fun) {
    return function(secondArg) {
        return function(firstArg) {
            return fun(firstArg, secondArg);
        };
    };
}

function div(n, d) {
    return n / d;
}
var div10 = curry2(div)(10);
console.log(div10(20));  //  2

## 4_currying.js
function curry3(fun) {
    return function(last) {
        return function(middle) {
            return function(first) {
                return fun(first, middle, last);
            };
        };
    };
}

function toHex(n) {
    var hex = n.toString(16);
    return (hex.length < 2) ? [0, hex].join('') : hex;
}
console.log(toHex(15)); //  0f
console.log(toHex(255)); //  ff

function rgbToHexString(r, g, b) {
    return ['#', toHex(r), toHex(g), toHex(b)].join('');
}
console.log(rgbToHexString(255, 255, 255)); //  #ffffff

var blueGreen = curry3(rgbToHexString)(255)(200);
console.log(blueGreen(1));  //  #01c8ff

## 5_部分適用.js
function partial1(fun, arg1) {
    return function(/* args */) {
        var args = [arg1].concat(_.toArray(arguments));
        return fun.apply(null, args);
    };
}

function div(n, d) {
    return n / d;
}

var over10Part1 = partial1(div, 10);
console.log(over10Part1(5));    //  2

## 6_部分適用.js
function partial2(fun, arg1, arg2) {
    return function(/* args */) {
        var args = [arg1].concat([arg2], _.toArray(arguments));
        return fun.apply(null, args);
    }
}

function toHex(n) {
    var hex = n.toString(16);
    return (hex.length < 2) ? [0, hex].join('') : hex;
}
console.log(toHex(15)); //  0f
console.log(toHex(255)); //  ff

function rgbToHexString(r, g, b) {
    return ['#', toHex(r), toHex(g), toHex(b)].join('');
}
console.log(rgbToHexString(255, 255, 255)); //  #ffffff

var redGreen = partial2(rgbToHexString, 1, 200);
console.log(redGreen(255));   //  #01c8ff

## 第一級関数.js
var func = function(){
    return 1;
};

[0, function(){return 1;}]

var a = {num: 1, fun: function(){return 2;}}

1 + (function(){return 1;})()

somefunc(1, function(){return 1;});

function func() {
    return function(){
        return 1;
    };
}

## 高階関数.js
function add(addValue, validator) {
    return function(n) {
        if (!validator(n)) {
            return NaN;
        }
        return n + addValue;
    };
}
	<!doctype html>
	<html>
	<head>
	<meta charset="utf8">
	<title>JavaScriptで学ぶ関数型プログラミングテストページ</title>
	</head>
	<body>
	<h1>JavaScriptで学ぶ関数型プログラミングのテストページ</h1>
	<script type="text/javascript" src="http://underscorejs.org/underscore.js"></script>
	<script type="text/javascript">

	// ここにコードを記述する

	</script>
	</body>
	</html>
	var ret = [];
	for (var i=0; i<10; i++) {
	var result = i * i;
	ret.push(result);
	}
	console.log(ret); // [0, 1, 4, 9, 16, 25, 36, 49, 64, 81]
	var squareUntil = function(limit) {
	return _.map(_.range(limit), function(n) {
	return n * n;
	});
	}
	console.log(squareUntil(10)); // [0, 1, 4, 9, 16, 25, 36, 49, 64, 81]
	function curry2(fun) {
	return function(secondArg) {
	return function(firstArg) {
	return fun(firstArg, secondArg);
	};
	};
	}

	function div(n, d) {
	return n / d;
	}
	var div10 = curry2(div)(10);
	console.log(div10(20)); // 2
	function curry3(fun) {
	return function(last) {
	return function(middle) {
	return function(first) {
	return fun(first, middle, last);
	};
	};
	};
	}

	function toHex(n) {
	var hex = n.toString(16);
	return (hex.length < 2) ? [0, hex].join('') : hex;
	}
	console.log(toHex(15)); // 0f
	console.log(toHex(255)); // ff

	function rgbToHexString(r, g, b) {
	return ['#', toHex(r), toHex(g), toHex(b)].join('');
	}
	console.log(rgbToHexString(255, 255, 255)); // #ffffff

	var blueGreen = curry3(rgbToHexString)(255)(200);
	console.log(blueGreen(1)); // #01c8ff
	function partial1(fun, arg1) {
	return function(/* args */) {
	var args = [arg1].concat(_.toArray(arguments));
	return fun.apply(null, args);
	};
	}

	function div(n, d) {
	return n / d;
	}

	var over10Part1 = partial1(div, 10);
	console.log(over10Part1(5)); // 2
	function partial2(fun, arg1, arg2) {
	return function(/* args */) {
	var args = [arg1].concat([arg2], _.toArray(arguments));
	return fun.apply(null, args);
	}
	}

	function toHex(n) {
	var hex = n.toString(16);
	return (hex.length < 2) ? [0, hex].join('') : hex;
	}
	console.log(toHex(15)); // 0f
	console.log(toHex(255)); // ff

	function rgbToHexString(r, g, b) {
	return ['#', toHex(r), toHex(g), toHex(b)].join('');
	}
	console.log(rgbToHexString(255, 255, 255)); // #ffffff

	var redGreen = partial2(rgbToHexString, 1, 200);
	console.log(redGreen(255)); // #01c8ff
	var func = function(){
	return 1;
	};

	[0, function(){return 1;}]

	var a = {num: 1, fun: function(){return 2;}}

	1 + (function(){return 1;})()

	somefunc(1, function(){return 1;});

	function func() {
	return function(){
	return 1;
	};
	}
	function add(addValue, validator) {
	return function(n) {
	if (!validator(n)) {
	return NaN;
	}
	return n + addValue;
	};
	}