Error Boundary

wybthon.error_boundary¶

error_boundary ¶

ErrorBoundary component for catching render errors in subtrees.

ErrorBoundary is a function component that installs an error handler on its owner scope. When a child render or effect raises, the boundary swaps in a fallback while leaving sibling trees untouched. It is the recommended way to surface unexpected errors without crashing the whole app.

ErrorBoundary ¶

ErrorBoundary(props: Any) -> Any

Catch render errors in children and display a fallback.

Parameters:

Name	Type	Description	Default
`props`	`Any`	The component's props with the following keys: `fallback`: A `VNode`, a string, or a callable `(error, reset) -> VNode`. The callable form may also accept just `(error,)`. `on_error`: Optional callback invoked with the caught exception (errors raised inside the callback are swallowed). `reset_key` / `reset_keys`: When this value (or callable result) changes, the boundary auto-clears the current error. `children`: Children rendered when no error is active.	required

Returns:

Type	Description
`Any`	A reactive `VNode` subtree that swaps to the
`Any`	fallback whenever a child raises.

What's in this module¶

ErrorBoundary catches render errors in its descendant subtree and renders a fallback in their place. Use it to isolate failures so a single broken widget can't take down the rest of the page.

Usage¶

from wybthon import ErrorBoundary, component
from wybthon.html import button, div, p


@component
def Profile(user_id):
    raise RuntimeError("not implemented")


@component
def Page():
    return ErrorBoundary(
        fallback=lambda err, reset: div(
            p("Something went wrong: ", str(err)),
            button("Try again", on_click=lambda _e: reset()),
        ),
        children=lambda: Profile(user_id=42),
    )

fallback receives the error and a reset() callback. Calling reset() clears the error and re-renders the children.
An on_error hook (if provided) lets you send the error to your monitoring stack.