title: $:/plugins/tiddlywiki/codemirror/readme

The CodeMirror plugin brings many features:

* Code colouring for many languages (see [[the official documentation here|http://codemirror.net/mode/index.html]])
* Auto closing brackets and tags
* Folding brackets, comments, and tags
* Auto-completion 

! Setting ~CodeMirror Content Types

You can determine which tiddler content types are edited by the ~CodeMirror widget by creating or modifying special tiddlers whose prefix is comprised of the string `$:/config/EditorTypeMappings/` concatenated with the content type. The text of that tiddler gives the editor type to be used (eg, ''text'', ''bitmap'', ''codemirror'').

The current editor type mappings are shown in [[$:/ControlPanel]] under the "Advanced" tab.

! ~CodeMirror Configuration

You can configure the ~CodeMirror plugin by creating a tiddler called [[$:/config/CodeMirror]] containing a JSON configuration object. The configuration tiddler must have its type field set to `application/json` to take effect.

See http://codemirror.net/ for details of available configuration options.

For example:

```
{
  "require": [
      "$:/plugins/tiddlywiki/codemirror/mode/javascript/javascript.js",
      "$:/plugins/tiddlywiki/codemirror/addon/dialog/dialog.js",
      "$:/plugins/tiddlywiki/codemirror/addon/search/searchcursor.js",
      "$:/plugins/tiddlywiki/codemirror/addon/edit/matchbrackets.js",
      "$:/plugins/tiddlywiki/codemirror/keymap/vim.js",
      "$:/plugins/tiddlywiki/codemirror/keymap/emacs.js"
  ],
  "configuration": {
      "keyMap": "vim",
      "matchBrackets":true,
      "showCursorWhenSelecting": true
  }
}
```

!! Basic working configuration

# Create a tiddler called `$:/config/CodeMirror`

# The type of the tiddler has to be set to `application/json`

# The text of the tiddler is the following: 

```
{
  "require": [
      "$:/plugins/tiddlywiki/codemirror/mode/javascript/javascript.js",
      "$:/plugins/tiddlywiki/codemirror/addon/edit/matchbrackets.js"
  ],
  "configuration": {
      "matchBrackets":true,
      "showCursorWhenSelecting": true
  }
}

```

# You should see line numbers when editing a tiddler
# When editing a tiddler, no matter what the type of the tiddler is set to, you should see matching brackets being highlighted whenever the cursor is next to one of them
# If you edit a tiddler with the type `application/javascript` or `application/json` you should see the code being syntax highlighted

!! Add HTML syntax highlighting

# Create a tiddler `$:/plugins/tiddlywiki/codemirror/mode/xml/xml.js`
## Add a field `module-type` and set it to ''library''
## Set the field `type` to ''application/javascript''
## Set the text field of the tiddler with the javascript code from this link : [[https://raw.githubusercontent.com/codemirror/CodeMirror/master/mode/xml/xml.js]]
# Set the text field of the tiddler `$:/config/CodeMirror` to:

```
{
  "require": [
      "$:/plugins/tiddlywiki/codemirror/mode/javascript/javascript.js",
      "$:/plugins/tiddlywiki/codemirror/mode/xml/xml.js",
      "$:/plugins/tiddlywiki/codemirror/addon/edit/matchbrackets.js"
  ],
  "configuration": {
      "showCursorWhenSelecting": true,
      "matchBrackets":true
  }
}
```
# Edit a tiddler with the type `text/html` and write some html code. You should see your code being coloured

!! Add a non-existing language mode

Here's an example of adding a new language mode - in this case, the language C.


# Create a tiddler `$:/plugins/tiddlywiki/codemirror/mode/clike/clike.js`
## Add a field `module-type` and set it to ''library''
## Set the field `type` to ''application/javascript''
## Set the text field of the tiddler with the javascript code from this link : [[https://raw.githubusercontent.com/codemirror/CodeMirror/master/mode/clike/clike.js]]
# Set the text field of the tiddler `$:/config/CodeMirror` to:

```
{
  "require": [
      "$:/plugins/tiddlywiki/codemirror/mode/javascript/javascript.js",
      "$:/plugins/tiddlywiki/codemirror/mode/clike/clike.js"
  ],
  "configuration": {
      "showCursorWhenSelecting": true
  }
}
```

# Add the correct ~EditorTypeMappings tiddler
## Find the matching MIME type. If you go on the [[CodeMirror documentation for language modes|http://codemirror.net/mode/index.html]] you can see the [[documentation for the c-like mode|http://codemirror.net/mode/clike/index.html]]. In this documentation, at the end you will be told the MIME types defined. Here it's ''text/x-csrc''
## Add the tiddler: `$:/config/EditorTypeMappings/text/x-csrc` and fill the text field with : ''codemirror''

If you edit a tiddler with the type `text/x-csrc` and write some code in C, you should see your text being coloured.

!! Add matching tags

# Add XML and HTML colouring
# Create a tiddler `$:/plugins/tiddlywiki/codemirror/addon/edit/matchtags.js`
## Add a field `module-type` and set it to ''library''
## Set the field `type` to ''application/javascript''
## Set the text field of the tiddler with the javascript code from this link : [[http://codemirror.net/addon/edit/matchtags.js]]
# Set the text field of the tiddler `$:/config/CodeMirror` to:

```
{
  "require": [
      "$:/plugins/tiddlywiki/codemirror/mode/javascript/javascript.js",
      "$:/plugins/tiddlywiki/codemirror/addon/edit/matchtags.js",
      "$:/plugins/tiddlywiki/codemirror/mode/xml/xml.js"
  ],
  "configuration": {
      "showCursorWhenSelecting": true,
      "matchTags": {"bothTags": true},
    "extraKeys": {"Ctrl-J": "toMatchingTag"}
  }
}
```

Edit a tiddler that has the type :`text/htm` and write this code:

```
<html>
      <div id="click here and press CTRL+J">
      <ul>
        <li>
        </li>
      </ul>
   </div>
</html>
```

If you click on a tag and press CTRL+J, your cursor will select the matching tag. Supposedly, it should highlight the pair when clicking a tag. However, that part doesn't work.

!! Adding closing tags

# Add the xml mode (see "Add XML and HTML colouring")
# Create a tiddler `$:/plugins/tiddlywiki/codemirror/addon/edit/closetags.js`
## Add a field `module-type` and set it to ''library''
## Set the field `type` to ''application/javascript''
## Set the text field of the tiddler with the javascript code from this link : [[http://codemirror.net/addon/edit/closetag.js]]

# Set the text field of the tiddler `$:/config/CodeMirror` to:

```
{
  "require": [
      "$:/plugins/tiddlywiki/codemirror/mode/javascript/javascript.js",
      "$:/plugins/tiddlywiki/codemirror/mode/xml/xml.js",
      "$:/plugins/tiddlywiki/codemirror/addon/edit/closetags.js"
  ],
  "configuration": {
      "showCursorWhenSelecting": true,
      "autoCloseTags":true
  }
}
```

If you edit a tiddler with the type`text/html` and write:

```
<html>
```

Then the closing tag ''</html>'' should automatically appear.

!! Add closing brackets

# Create a tiddler `$:/plugins/tiddlywiki/codemirror/addon/edit/closebrackets.js`
## Add a field `module-type` and set it to ''library''
## Set the field `type` to ''application/javascript''
## Set the text field of the tiddler with the javascript code from this link : [[http://codemirror.net/addon/edit/closebrackets.js]]
# Set the text field of the tiddler `$:/config/CodeMirror` to:

```
{
  "require": [
      "$:/plugins/tiddlywiki/codemirror/mode/javascript/javascript.js",
      "$:/plugins/tiddlywiki/codemirror/addon/edit/matchbrackets.js",
      "$:/plugins/tiddlywiki/codemirror/addon/edit/closebrackets.js"
  ],

  "configuration": {

      "showCursorWhenSelecting": true,
      "matchBrackets":true,
      "autoCloseBrackets":true
  }
}
```

# If you try to edit any tiddler and write `if(` you should see the bracket closing itself automatically (you will get "if()"). It works with (), [], and {}
# If you try and edit a tiddler with the type `application/javascript`, it will auto-close `()`,`[]`,`{}`,`''` and `""`

!! Adding folding tags

# Create a tiddler `$:/plugins/tiddlywiki/codemirror/addon/fold/foldcode.js`
## Add a field `module-type` and set it to ''library''
## Set the field `type` to ''application/javascript''
## Set the text field of the tiddler with the javascript code from this link : [[http://codemirror.net/addon/fold/foldcode.js]]
# Repeat the above process for the following tiddlers, but replace the code with the one from the given link:
## Create a tiddler `$:/plugins/tiddlywiki/codemirror/addon/fold/xml-fold.js`, the code can be found here [[https://raw.githubusercontent.com/codemirror/CodeMirror/master/addon/fold/xml-fold.js]]
## Create a tiddler `$:/plugins/tiddlywiki/codemirror/addon/fold/foldgutter.js`, the code can be found here [[http://codemirror.net/addon/fold/foldgutter.js]]
# Create a tiddler `$:/plugins/tiddlywiki/codemirror/addon/fold/foldgutter.css`
## Add the tag ''$:/tags/Stylesheet''
## Set the text field of the tiddler with the css code from this link : [[http://codemirror.net/addon/fold/foldgutter.css]]

# Set the text field of the tiddler `$:/config/CodeMirror` to:

```
{
  "require": [
      "$:/plugins/tiddlywiki/codemirror/mode/javascript/javascript.js",
      "$:/plugins/tiddlywiki/codemirror/mode/xml/xml.js",
      "$:/plugins/tiddlywiki/codemirror/addon/fold/foldcode.js",
      "$:/plugins/tiddlywiki/codemirror/addon/fold/xml-fold.js",
      "$:/plugins/tiddlywiki/codemirror/addon/fold/foldgutter.js"
  ],
  "configuration": {
      "showCursorWhenSelecting": true,
      "matchTags": {"bothTags": true},
      "foldGutter": true,
      "gutters": ["CodeMirror-linenumbers", "CodeMirror-foldgutter"]
  }
}

```

Now if you type the below code in a tiddler with the type `text/html`:

```
<html>
   <div>
      <ul>

      </ul>
   </div>
</html>
```

You should see little arrows just next to the line numbers. Clicking on it will have the effect to fold the code (or unfold it).