diff options
Diffstat (limited to 'docs/source/highlighting.rst')
-rw-r--r-- | docs/source/highlighting.rst | 58 |
1 files changed, 58 insertions, 0 deletions
diff --git a/docs/source/highlighting.rst b/docs/source/highlighting.rst new file mode 100644 index 0000000..260cfbe --- /dev/null +++ b/docs/source/highlighting.rst @@ -0,0 +1,58 @@ +Highlighting +============ + +Rich can apply styles to patterns in text which you :meth:`~rich.console.Console.print` or :meth:`~rich.console.Console.log`. With the default settings, Rich will highlight things such as numbers, strings, collections, booleans, None, and a few more exotic patterns such as file paths, URLs and UUIDs. + +You can disable highlighting either by setting ``highlight=False`` on :meth:`~rich.console.Console.print` or :meth:`~rich.console.Console.log`, or by setting ``highlight=False`` on the :class:`~rich.console.Console` constructor which disables it everywhere. If you disable highlighting on the constructor, you can still selectively *enable* highlighting with ``highlight=True`` on print/log. + +Custom Highlighters +------------------- + +If the default highlighting doesn't fit your needs, you can define a custom highlighter. The easiest way to do this is to extend the :class:`~rich.highlighter.RegexHighlighter` class which applies a style to any text matching a list of regular expressions. + +Here's an example which highlights text that looks like an email address:: + + from rich.console import Console + from rich.highlighter import RegexHighlighter + from rich.theme import Theme + + class EmailHighlighter(RegexHighlighter): + """Apply style to anything that looks like an email.""" + + base_style = "example." + highlights = [r"(?P<email>[\w-]+@([\w-]+\.)+[\w-]+)"] + + + theme = Theme({"example.email": "bold magenta"}) + console = Console(highlighter=EmailHighlighter(), theme=theme) + console.print("Send funds to money@example.org") + + +The ``highlights`` class variable should contain a list of regular expressions. The group names of any matching expressions are prefixed with the ``base_style`` attribute and used as styles for matching text. In the example above, any email addresses will have the style "example.email" applied, which we've defined in a custom :ref:`Theme <themes>`. + +Setting the highlighter on the Console will apply highlighting to all text you print (if enabled). You can also use a highlighter on a more granular level by using the instance as a callable and printing the result. For example, we could use the email highlighter class like this:: + + + console = Console(theme=theme) + highlight_emails = EmailHighlighter() + console.print(highlight_emails("Send funds to money@example.org")) + + +While :class:`~rich.highlighter.RegexHighlighter` is quite powerful, you can also extend its base class :class:`~rich.highlighter.Highlighter` to implement a custom scheme for highlighting. It contains a single method :class:`~rich.highlighter.Highlighter.highlight` which is passed the :class:`~rich.text.Text` to highlight. + +Here's a silly example that highlights every character with a different color:: + + from random import randint + + from rich import print + from rich.highlighter import Highlighter + + + class RainbowHighlighter(Highlighter): + def highlight(self, text): + for index in range(len(text)): + text.stylize(f"color({randint(16, 255)})", index, index + 1) + + + rainbow = RainbowHighlighter() + print(rainbow("I must not fear. Fear is the mind-killer.")) |