Contando palabras en cadena

/*Redirect console output to HTML.*/document.body.innerHTML='';console.log=function(s){document.body.innerHTML+=s+'\n';};
/*String format.*/String.format||(String.format=function(f){return function(a){return f.replace(/{(\d+)}/g,function(m,n){return"undefined"!=typeof a[n]?a[n]:m})}([].slice.call(arguments,1))});

// ^ IGNORE CODE ABOVE ^
//   =================

// Clean and match sub-strings in a string.
function extractSubstr(str, regexp) {
    return str.replace(/[^\w\s]|_/g, '')
        .replace(/\s+/g, ' ')
        .toLowerCase().match(regexp) || [];
}

// Find words by searching for sequences of non-whitespace characters.
function getWordsByNonWhiteSpace(str) {
    return extractSubstr(str, /\S+/g);
}

// Find words by searching for valid characters between word-boundaries.
function getWordsByWordBoundaries(str) {
    return extractSubstr(str, /\b[a-z\d]+\b/g);
}

// Example of usage.
var edisonQuote = "I have not failed. I've just found 10,000 ways that won't work.";
var words1 = getWordsByNonWhiteSpace(edisonQuote);
var words2 = getWordsByWordBoundaries(edisonQuote);

console.log(String.format('"{0}" - Thomas Edison\n\nWord count via:\n', edisonQuote));
console.log(String.format(' - non-white-space: ({0}) [{1}]', words1.length, words1.join(', ')));
console.log(String.format(' - word-boundaries: ({0}) [{1}]', words2.length, words2.join(', ')));

body { font-family: monospace; white-space: pre; font-size: 11px; }

function cleanString(str) {
    return str.replace(/[^\w\s]|_/g, '')
        .replace(/\s+/g, ' ')
        .toLowerCase();
}

function extractSubstr(str, regexp) {
    return cleanString(str).match(regexp) || [];
}

function getWordsByNonWhiteSpace(str) {
    return extractSubstr(str, /\S+/g);
}

function getWordsByWordBoundaries(str) {
    return extractSubstr(str, /\b[a-z\d]+\b/g);
}

function wordMap(str) {
    return getWordsByWordBoundaries(str).reduce(function(map, word) {
        map[word] = (map[word] || 0) + 1;
        return map;
    }, {});
}

function mapToTuples(map) {
    return Object.keys(map).map(function(key) {
        return [ key, map[key] ];
    });
}

function mapToSortedTuples(map, sortFn, sortOrder) {
    return mapToTuples(map).sort(function(a, b) {
        return sortFn.call(undefined, a, b, sortOrder);
    });
}

function countWords(str) {
    return getWordsByWordBoundaries(str).length;
}

function wordFrequency(str) {
    return mapToSortedTuples(wordMap(str), function(a, b, order) {
        if (b[1] > a[1]) {
            return order[1] * -1;
        } else if (a[1] > b[1]) {
            return order[1] * 1;
        } else {
            return order[0] * (a[0] < b[0] ? -1 : (a[0] > b[0] ? 1 : 0));
        }
    }, [1, -1]);
}

function printTuples(tuples) {
    return tuples.map(function(tuple) {
        return padStr(tuple[0], ' ', 12, 1) + ' -> ' + tuple[1];
    }).join('\n');
}

function padStr(str, ch, width, dir) { 
    return (width <= str.length ? str : padStr(dir < 0 ? ch + str : str + ch, ch, width, dir)).substr(0, width);
}

function toTable(data, headers) {
    return $('<table>').append($('<thead>').append($('<tr>').append(headers.map(function(header) {
        return $('<th>').html(header);
    })))).append($('<tbody>').append(data.map(function(row) {
        return $('<tr>').append(row.map(function(cell) {
            return $('<td>').html(cell);
        }));
    })));
}

function addRowsBefore(table, data) {
    table.find('tbody').prepend(data.map(function(row) {
        return $('<tr>').append(row.map(function(cell) {
            return $('<td>').html(cell);
        }));
    }));
    return table;
}

$(function() {
    $('#countWordsBtn').on('click', function(e) {
        var str = $('#wordsTxtAra').val();
        var wordFreq = wordFrequency(str);
        var wordCount = countWords(str);
        var uniqueWords = wordFreq.length;
        var summaryData = [
            [ 'TOTAL', wordCount ],
            [ 'UNIQUE', uniqueWords ]
        ];
        var table = toTable(wordFreq, ['Word', 'Frequency']);
        addRowsBefore(table, summaryData);
        $('#wordFreq').html(table);
    });
});

table {
    border-collapse: collapse;
    table-layout: fixed;
    width: 200px;
    font-family: monospace;
}
thead {
    border-bottom: #000 3px double;;
}
table, td, th {
    border: #000 1px solid;
}
td, th {
    padding: 2px;
    width: 100px;
    overflow: hidden;
}

textarea, input[type="button"], table {
    margin: 4px;
    padding: 2px;
}

<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>

<h1>Word Frequency</h1>
<textarea id="wordsTxtAra" cols="60" rows="8">Four score and seven years ago our fathers brought forth on this continent, a new nation, conceived in Liberty, and dedicated to the proposition that all men are created equal.

Now we are engaged in a great civil war, testing whether that nation, or any nation so conceived and so dedicated, can long endure. We are met on a great battle-field of that war. We have come to dedicate a portion of that field, as a final resting place for those who here gave their lives that that nation might live. It is altogether fitting and proper that we should do this.

But, in a larger sense, we can not dedicate -- we can not consecrate -- we can not hallow -- this ground. The brave men, living and dead, who struggled here, have consecrated it, far above our poor power to add or detract. The world will little note, nor long remember what we say here, but it can never forget what they did here. It is for us the living, rather, to be dedicated here to the unfinished work which they who fought here have thus far so nobly advanced. It is rather for us to be here dedicated to the great task remaining before us -- that from these honored dead we take increased devotion to that cause for which they gave the last full measure of devotion -- that we here highly resolve that these dead shall not have died in vain -- that this nation, under God, shall have a new birth of freedom -- and that government of the people, by the people, for the people, shall not perish from the earth.</textarea><br />
<input type="button" id="countWordsBtn" value="Count Words" />
<div id="wordFreq"></div>

var calculate = function() {
  var string = document.getElementById('input').value;
  var length = string.split(/[^\s]+/).length - 1;
  document.getElementById('count').innerHTML = length;
};

<textarea id="input">My super text that does 7 words.</textarea>
<button onclick="calculate()">Calculate</button>
<span id="count">7</span> words

var str = "Random String";
var wordCount = _.size(_.words(str));
console.log(wordCount);

<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.11/lodash.min.js"></script>

// This is the fastest at 111,037 ops/s ±2.86% fastest
var str = "All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy.";
function WordCount(str) {
  return str.split(" ").length;
}
console.log(WordCount(str));
// Returns 241 words. Not the same as Microsoft Word count, of by one.

// This is the 2nd fastest at 46,835 ops/s ±1.76% 57.82% slower
var str = "All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy.";
function WordCount(str) {
  return str.split(/(?!\W)\S+/).length;
}
console.log(WordCount(str));
// Returns 241 words. Not the same as Microsoft Word count, of by one.

// This is the 3rd fastest at 37,121 ops/s ±1.18% 66.57% slower
var str = "All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy.";
function countWords(str) {
  var str = str.replace(/\S+/g,"\+1");
  return eval(str);
}
console.log(countWords(str));
// Returns 240 words. Same as Microsoft Word count.

// This is the slowest at 89 ops/s 17,270 ops/s ±2.29% 84.45% slower
var str = "All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy.";
function countWords(str) {
  var str = str.replace(/(?!\W)\S+/g,"1").replace(/\s*/g,"");
  return str.lastIndexOf("");
}
console.log(countWords(str));
// Returns 240 words. Same as Microsoft Word count.

 function NumberOf() { 
		 var string = "Write a piece of code in any language of your choice that computes the total number of characters, words and lines in a given text. \n This is second line. \n This is third line.";

		 var length = string.length; //No of characters
		 var words = string.match(/\w+/g).length; //No of words
		 var lines = string.split(/\r\n|\r|\n/).length; // No of lines

		 console.log('Number of characters:',length);
		 console.log('Number of words:',words);
		 console.log('Number of lines:',lines);


}

NumberOf();