[jQuery] autocompleter matching requirement

autocompleter_init.js

var config = {
            labelField: '#label_input'
            valueField: '#value_input',
            source: '/path_to_autocompleter_backend', //responds with json [{label: '...', value: '...'}, {label: '...', value: '...'}]
            focus: function(event, ui) {
                var self = config;
                $(self.field).val( ui.item.label );
                return false;
            },
            change: function(event, ui){
                var self = config;
                if ($(self.valueField).val() == '') {
                    $(self.labelField).val('')
                }
            },
            select: function(event, ui){
                var self = config;
                $(self.valueField).val( ui.item.value );
                $(self.labelField).val( ui.item.label );
                return false;
            },
            create: function(event, ui) {
                var self = config;
                $(self.labelField).keydown(function(e){
                    var notPermittedKeyCodes = [8,32,46];
                    var keyCode = parseInt(e.keyCode);
                    if ($.inArray(keyCode, notPermittedKeyCodes) != -1 || keyCode > 46)
                        $(self.valueField).val('');
                });
            };

$(config.labelField).autocomplete(config);