textual.suggester

Contains the Suggester class, used by the Input widget.

SuggestFromList

SuggestFromList(suggestions, *, case_sensitive=True)

Bases: Suggester

Give completion suggestions based on a fixed list of options.

Example

countries = ["England", "Scotland", "Portugal", "Spain", "France"]

class MyApp(App[None]):
    def compose(self) -> ComposeResult:
        yield Input(suggester=SuggestFromList(countries, case_sensitive=False))

If the user types P inside the input widget, a completion suggestion for "Portugal" appears.

Parameters:

Name	Type	Description	Default
suggestions	Iterable[str]	Valid suggestions sorted by decreasing priority.	required
case_sensitive	bool	Whether suggestions are computed in a case sensitive manner or not. The values provided in the argument suggestions represent the canonical representation of the completions and they will be suggested with that same casing.	True

get_suggestion async

get_suggestion(value)

Gets a completion from the given possibilities.

Parameters:

Name	Type	Description	Default
value	str	The current value.	required

Returns:

Type	Description
str | None	A valid completion suggestion or None.

Suggester

Suggester(*, use_cache=True, case_sensitive=False)

Bases: ABC

Defines how widgets generate completion suggestions.

To define a custom suggester, subclass Suggester and implement the async method get_suggestion. See SuggestFromList for an example.

Parameters:

Name	Type	Description	Default
use_cache	bool	Whether to cache suggestion results.	True
case_sensitive	bool	Whether suggestions are case sensitive or not. If they are not, incoming values are casefolded before generating the suggestion.	False

cache instance-attribute

cache: LRUCache[str, str | None] | None = (
    LRUCache(1024) if use_cache else None
)

Suggestion cache, if used.

get_suggestion abstractmethod async

get_suggestion(value)

Try to get a completion suggestion for the given input value.

Custom suggesters should implement this method.

Note

The value argument will be casefolded if self.case_sensitive is False.

Note

If your implementation is not deterministic, you may need to disable caching.

Parameters:

Name	Type	Description	Default
value	str	The current value of the requester widget.	required

Returns:

Type	Description
str | None	A valid suggestion or None.

SuggestionReady dataclass

Bases: Message

Sent when a completion suggestion is ready.

suggestion instance-attribute

suggestion: str

The string suggestion.

value instance-attribute

value: str

The value to which the suggestion is for.