Fix #104 cannot initialize operators with zero input

Author: mistic100

src/core.js

@@ -489,7 +489,9 @@ QueryBuilder.prototype.updateRuleOperator = function(rule, previousOperator) {
         if ($valueContainer.is(':empty') || rule.operator.nb_inputs !== previousOperator.nb_inputs) {
             this.createRuleInput(rule);
         }
+    }
 
+    if (rule.operator) {
         rule.$el.find('.rule-operator-container [name$=_operator]').val(rule.operator.type);
     }
 

src/public.js

@@ -212,9 +212,6 @@ QueryBuilder.prototype.setRules = function(data) {
                 if (rule.id === undefined) {
                     error('Missing rule field id');
                 }
-                if (rule.value === undefined) {
-                    rule.value = '';
-                }
                 if (rule.operator === undefined) {
                     rule.operator = 'equal';
                 }
@@ -232,7 +229,7 @@ QueryBuilder.prototype.setRules = function(data) {
                     model.data = rule.data;
                 }
 
-                if (model.operator.nb_inputs !== 0) {
+                if (model.operator.nb_inputs !== 0 && rule.value !== undefined) {
                     that.setRuleValue(model, rule.value);
                 }
             }