LiteralInput

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import panel as pn
pn.extension()

The LiteralInput widget allows entering any Python literal using a text entry box whose contents are then parsed in Python. The widget only supports Python literal types. Optionally a type may be declared to validate the literal before updating the parameter.

Discover more on using widgets to add interactivity to your applications in the how-to guides on interactivity. Alternatively, learn how to set up callbacks and (JS-)links between parameters or how to use them as part of declarative UIs with Param.

Parameters:

For details on other options for customizing the component see the layout and styling how-to guides.

Core

• serializer (str[‘ast’, ‘json]): The serialization (and deserialization) method to use. ‘ast’ uses ast.literal_eval and ‘json’ uses json.loads and json.dumps.

• type (type or tuple(type)): A Python literal type (e.g. list, dict, set, int, float, bool, str)

• value: Parsed value of the indicated type

Display

• disabled (boolean): Whether the widget is editable

• name (str): The title of the widget

• placeholder (str): A placeholder string displayed when no value is entered

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literal_input = pn.widgets.LiteralInput(name='Literal Input (dict)', value={'key': [1, 2, 3]}, type=dict)
literal_input

LiteralInput.value returns a value of the evaluated type that can be read out and set like other widgets:

literal_input.value

{'key': [1, 2, 3]}

Controls

The LiteralInput widget exposes a number of options which can be changed from both Python and Javascript. Try out the effect of these parameters interactively:

pn.Row(literal_input.controls(jslink=True), literal_input)

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