Minor changes according to discussion in !30

src/views/form/inputGroup.js

@@ -13,7 +13,7 @@ export default class InputGroup {
   view(vnode) {
     // set display-settings accoridng to error-state
     let errorField = null;
-    let groupClasses = vnode.attrs.classes ? vnode.attrs.classes : '';
+    let groupClasses = vnode.attrs.classes || '';
     const errors = this.getErrors();
     if (errors.length > 0) {
       errorField = m('span', `Error: ${errors.join(', ')}`);
@@ -37,15 +37,13 @@ export default class InputGroup {
       ]);
     }
     args.list = `${vnode.attrs.name}-datalist`;
-    if (typeof args.getSuggestions === 'function') {
+    if (args.getSuggestions) {
       args.oninput_original = args.oninput;
       args.oninput = (e) => {
-        if (typeof args.getSuggestions === 'function') {
-          args.getSuggestions(e.target.value, (result) => {
-            this.suggestions = result;
-          });
-        }
-        if (typeof args.oninput_original === 'function') {
+        args.getSuggestions(e.target.value, (result) => {
+          this.suggestions = result;
+        });
+        if (args.oninput_original) {
           args.oninput_original(e);
         }
       };

src/views/form/jsonSchemaForm.js

 import m from 'mithril';
 import Ajv from 'ajv';
 import jsonSchemaDraft04 from 'ajv/lib/refs/json-schema-draft-04.json';
-import { isNullOrUndefined } from 'util';
 import { log } from '../../models/log';
 import inputGroup from './inputGroup';
 import selectGroup from './selectGroup';
@@ -27,7 +26,7 @@ export default class JSONSchemaForm {
     } else {
       this.ajv.addSchema(this.schema, 'schema');
     }
-    if (isNullOrUndefined(this.fieldOrder)) {
+    if (!this.fieldOrder) {
       this.fieldOrder = [];
     }
   }