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Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

      <th>Population (M)</th>
      <th>GNP (B)</th>
    <tr><td>United Kingdom</td><td>64.231</td><td>2290</td></tr>
 *Functional JavaScript for crawling the Web

/*************************************************** *
 * Helper Fantion

function logs(){
	return arguments;

function nodes(sel, root){
	return (root || document).querySelectorAll(sel);

function finder(selector) {
  return function(root) {
    return nodes(selector, root);

function map(fn, iterable){
	return [].map.call(iterable, fn)

function prop(name){
	return function(object){
		return object[name];

function sequence() {
	var fns = Array.prototype.slice.call(arguments);
	return fns.reduce(function(comp, fn) {
		return function(){
			var args =  Array.prototype.slice.call(arguments);
			return comp(fn.apply(null, args))

//隣り合う 2 つの配列要素に対して(左から右へ)同時に関数を適用
function reduce(fn, init, iterable){
	return [].reduce.call(iterable, fn, init)

function compose(){
	var fns = Array.prototype.slice.call(arguments);
	return sequence.apply(null, fns.reverse());

function curry( orig_func ) {
	var ap = Array.prototype;
	var args = arguments;
	function fn() {
		ap.push.apply( fn.args, arguments );
		return fn.args.length < orig_func.length
		  ? fn
		  : orig_func.apply( this, fn.args );
	return function() {
		fn.args = ap.slice.call( args, 1 );
		return fn.apply( this, arguments );

function partial( orig_func ) {
	var aps = Array.prototype.slice,
	args = aps.call( arguments, 1 );
	return function() {
		return orig_func.apply( this, args.concat( aps.call( arguments ) ) );

 * 以下、main

var  rows = nodes("tbody tr");
var findCells = finder("td");
var getText = prop("textContent");

var getFirst = prop(0);
var getSecond = prop(1);
var getThird = prop(2);

 * テーブルの1行目(国名)を取得
console.log( "first-ColumnList", map(compose(findCells, getFirst, getText), rows) )

 * 途中の処理にlogsを挟んでデバッグ
console.log( "debug", map(compose(findCells, getFirst, logs, getText), rows) )

 * 人口の合計を取得
var sum = function(a, b) {
	return a + b;
var populations  =  map(compose(findCells, getSecond, getText, parseFloat), rows);
console.log("sum-populations", reduce(sum, 0, populations));

 * データをオブジェクトに変換
var asObject = function(data){
	return {
		population: parseFloat(getSecond(data)),
var getTexts = partial(map, getText); //getText関数をmap関数に部分適用して、arrayにgetTextを使えるようにする
console.log("toObject",  map(compose(findCells, getTexts, asObject), rows ))

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