JavaScript pluralize an english string

Question

In PHP, I use Kuwamoto\'s class to pluralize nouns in my strings. I didn\'t find something as good as this script in javascript except for some plugins. So, it would be grea

Answer 1

So, I answer my own question by sharing my translation in javascript of Kuwamoto's PHP class.

String.prototype.plural = function(revert){

    var plural = {
        '(quiz)$'               : "$1zes",
        '^(ox)$'                : "$1en",
        '([m|l])ouse$'          : "$1ice",
        '(matr|vert|ind)ix|ex$' : "$1ices",
        '(x|ch|ss|sh)$'         : "$1es",
        '([^aeiouy]|qu)y$'      : "$1ies",
        '(hive)$'               : "$1s",
        '(?:([^f])fe|([lr])f)$' : "$1$2ves",
        '(shea|lea|loa|thie)f$' : "$1ves",
        'sis$'                  : "ses",
        '([ti])um$'             : "$1a",
        '(tomat|potat|ech|her|vet)o$': "$1oes",
        '(bu)s$'                : "$1ses",
        '(alias)$'              : "$1es",
        '(octop)us$'            : "$1i",
        '(ax|test)is$'          : "$1es",
        '(us)$'                 : "$1es",
        '([^s]+)$'              : "$1s"
    };

    var singular = {
        '(quiz)zes$'             : "$1",
        '(matr)ices$'            : "$1ix",
        '(vert|ind)ices$'        : "$1ex",
        '^(ox)en$'               : "$1",
        '(alias)es$'             : "$1",
        '(octop|vir)i$'          : "$1us",
        '(cris|ax|test)es$'      : "$1is",
        '(shoe)s$'               : "$1",
        '(o)es$'                 : "$1",
        '(bus)es$'               : "$1",
        '([m|l])ice$'            : "$1ouse",
        '(x|ch|ss|sh)es$'        : "$1",
        '(m)ovies$'              : "$1ovie",
        '(s)eries$'              : "$1eries",
        '([^aeiouy]|qu)ies$'     : "$1y",
        '([lr])ves$'             : "$1f",
        '(tive)s$'               : "$1",
        '(hive)s$'               : "$1",
        '(li|wi|kni)ves$'        : "$1fe",
        '(shea|loa|lea|thie)ves$': "$1f",
        '(^analy)ses$'           : "$1sis",
        '((a)naly|(b)a|(d)iagno|(p)arenthe|(p)rogno|(s)ynop|(t)he)ses$': "$1$2sis",        
        '([ti])a$'               : "$1um",
        '(n)ews$'                : "$1ews",
        '(h|bl)ouses$'           : "$1ouse",
        '(corpse)s$'             : "$1",
        '(us)es$'                : "$1",
        's$'                     : ""
    };

    var irregular = {
        'move'   : 'moves',
        'foot'   : 'feet',
        'goose'  : 'geese',
        'sex'    : 'sexes',
        'child'  : 'children',
        'man'    : 'men',
        'tooth'  : 'teeth',
        'person' : 'people'
    };

    var uncountable = [
        'sheep', 
        'fish',
        'deer',
        'moose',
        'series',
        'species',
        'money',
        'rice',
        'information',
        'equipment'
    ];

    // save some time in the case that singular and plural are the same
    if(uncountable.indexOf(this.toLowerCase()) >= 0)
      return this;

    // check for irregular forms
    for(word in irregular){

      if(revert){
              var pattern = new RegExp(irregular[word]+'$', 'i');
              var replace = word;
      } else{ var pattern = new RegExp(word+'$', 'i');
              var replace = irregular[word];
      }
      if(pattern.test(this))
        return this.replace(pattern, replace);
    }

    if(revert) var array = singular;
         else  var array = plural;

    // check for matches using regular expressions
    for(reg in array){

      var pattern = new RegExp(reg, 'i');

      if(pattern.test(this))
        return this.replace(pattern, array[reg]);
    }

    return this;
}

Easy to use:

alert("page".plural()); // return plural form => pages
alert("mouse".plural()); // return plural form => mice
alert("women".plural(true)); // return singular form => woman

DEMO