JSFiddle - React, Tailwind, and code Playground

HTML

<script src="http://digitarald.de/project/autocompleter/1-1/source/Observer.js"></script>
<script src="http://digitarald.de/project/autocompleter/1-1/source/Autocompleter.js"></script>
<link rel="stylesheet" href="http://digitarald.de/css/blueprint/screen.css">
<link rel="stylesheet" href="http://digitarald.de/css/site.css">
<link rel="stylesheet" href="http://digitarald.de/project/autocompleter/1-1/assets/Autocompleter.css">
<form action="./" method="get" id="form-demo">
    <fieldset>
        
        <legend>Choose a country name?</legend>
        <label>
            <input type="text" name="local" class="title" id="demo-local" />
        </label>
        
        <label>
            <span>Mode: pick</span>
            <input type="text" name="local2" class="title" id="demo-local2" />
        </label>
        
        <label>
            <span>Mode: type-ahead</span>
            <input type="text" name="local3" class="title" id="demo-local3" />
        </label>
        
        <label>
            <span>Custom choices creation</span>
            <input type="text" name="local4" class="title" id="demo-local4" />
        </label>
        
    </fieldset>
</form>

CSS

.demo-info
{
    position:            absolute;
    top:                0;
    right:                4px;
    padding:            1px 2px;
    font-size:            0.9em;
    color:                #888;
}

JavaScript

Autocompleter.Local = new Class({

    Extends: Autocompleter,

    options: {
        minLength: 0,
        delay: 200
    },

    initialize: function(element, tokens, options) {
        this.parent(element, options);
        this.tokens = tokens;
    },

    query: function() {
        this.update(this.filter());
    }

});

// Test source, list of countries
var tokens = ['Afghanistan', 'Ă…land Islands', 'Albania', 'Algeria', 'American Samoa', 'Andorra', 'Angola', 'Anguilla', 'Antarctica', 'Antigua And Barbuda', 'Argentina', 'Armenia', 'Aruba', 'Australia', 'Austria', 'Azerbaijan', 'Bahamas', 'Bahrain', 'Bangladesh', 'Barbados', 'Belarus', 'Belgium', 'Belize', 'Benin', 'Bermuda', 'Bhutan', 'Bolivia', 'Bosnia And Herzegovina', 'Botswana', 'Bouvet Island', 'Brazil', 'British Indian Ocean Territory', 'Brunei Darussalam', 'Bulgaria', 'Burkina Faso', 'Burundi', 'Cambodia', 'Cameroon', 'Canada', 'Cape Verde', 'Cayman Islands', 'Central African Republic', 'Chad', 'Chile', 'China', 'Christmas Island', 'Cocos (Keeling) Islands', 'Colombia', 'Comoros', 'Congo', 'Congo, The Democratic Republic Of The', 'Cook Islands', 'Costa Rica', 'Cote D\'ivoire', 'Croatia', 'Cuba', 'Cyprus', 'Czech Republic', 'Denmark', 'Djibouti', 'Dominica', 'Dominican Republic', 'Ecuador', 'Egypt', 'El Salvador', 'Equatorial Guinea', 'Eritrea', 'Estonia', 'Ethiopia', 'Falkland Islands (Malvinas)', 'Faroe Islands', 'Fiji', 'Finland', 'France', 'French Guiana', 'French Polynesia', 'French Southern Territories', 'Gabon', 'Gambia', 'Georgia', 'Germany', 'Ghana', 'Gibraltar', 'Greece', 'Greenland', 'Grenada', 'Guadeloupe', 'Guam', 'Guatemala', 'Guernsey', 'Guinea', 'Guinea-Bissau', 'Guyana', 'Haiti', 'Heard Island And Mcdonald Islands', 'Holy See (Vatican City State)', 'Honduras', 'Hong Kong', 'Hungary', 'Iceland', 'India', 'Indonesia', 'Iran, Islamic Republic Of', 'Iraq', 'Ireland', 'Isle Of Man', 'Israel', 'Italy', 'Jamaica', 'Japan', 'Jersey', 'Jordan', 'Kazakhstan', 'Kenya', 'Kiribati', 'Korea,...