Been trying to decide between using CodeMirror or Ace editor. I've been leaning towards CodeMirror, however there's one feature of Ace that I really like and that is how it does syntax validation. So as I'm typing there can appear a warning or error icon in the left gutter area beside the line number, and when I hover over it it gives me a little description.

Is there any way to get this functionality in CodeMirror? Specifically, I'm using the css mode for CodeMirror.

It'd also be nice to be able to add in my own custom validation.

Thanks.

Been trying to decide between using CodeMirror or Ace editor. I've been leaning towards CodeMirror, however there's one feature of Ace that I really like and that is how it does syntax validation. So as I'm typing there can appear a warning or error icon in the left gutter area beside the line number, and when I hover over it it gives me a little description.

Is there any way to get this functionality in CodeMirror? Specifically, I'm using the css mode for CodeMirror.

It'd also be nice to be able to add in my own custom validation.

Thanks.

• javascript
• validation
• syntax-highlighting
• codemirror
• ace-editor

2 Answers 2

see http://codemirror.net/3/demo/widget.html for a nice demo.

but ace have other nice features too. For me deciding factors were multiple cursors and indentGuides

For Ace adding your own validation function is quite simple.Here is how we added validation for CSS using CSSLint:

https://github.com/ajaxorg/ace/blob/master/lib/ace/mode/css_worker.js https://github.com/ajaxorg/ace/blob/master/lib/ace/mode/css.js#L78