# Code blocks

Code block directives are for displaying code. By default the code is copyable and includes a copy icon.
To keep code snippets neat, separate the display from the command.
This keeps the command copyable without having the screen return inside the command.

## Basic usage

For example using the rst code block before a restructuredText example:

`.. code-block:: rst` when used with the `.. tip:: here's a tip` as shown above, renders as:

```rst
.. tip:: here's a tip
```

The code block directive can be changed to a language which is supported by restructuredText.
For example, the following code-block is cql. If you add the following code block directive, to the code sample below:

`.. code-block:: cql`

```cql
create_keyspace_statement: CREATE KEYSPACE [ IF NOT EXISTS ] `keyspace_name` WITH `options`
```

You see that there is syntax highlighting.

The key item to remember is that the entire code block needs **three** spaces before any line. The code will automatically be highlighted.
You can create code-blocks in any of the following [languages](https://pygments.org/languages/). Using `none` is also acceptable. If you use none, there is no syntax highlighting.

```none
create_keyspace_statement: CREATE KEYSPACE [ IF NOT EXISTS ] `keyspace_name` WITH `options`
```

If you are including a large example (an entire file) as a code-block, refer to [Literal Include](https://sphinx-theme.scylladb.com/master/examples/includes.md).

## Show line number

To show the line number, add the option :linenos: to the code-block directive.

For example:

```rst
.. code-block:: rst
   :linenos:

   Line 1
   Line 2
```

Renders:

```rst
Line 1
Line 2
```

## Hide copy button

Add the class `hide-copy-button` to the `code-block` directive to hide the copy button.

For example:

```rst
.. code-block:: rst
   :class: hide-copy-button

   .. tip:: here's a tip
```

Renders:

```rst
.. tip:: here's a tip
```

## Highlight lines

To highlight lines, add the option :emphasize-lines: <number> to the code-block directive.

For example:

```rst
.. code-block:: rst
   :emphasize-lines: 1,3

   Line 1
   Line 2
   Line 3
```

Renders:

```rst
Line 1
Line 2
Line 3
```