Prompt for numeric entry only

[jamesmcm]

Hi,

I'd like to create a prompt which only accepts numeric entries, i.e. any non-numeric character key-presses do not register (or optionally, trigger the bell).

Is there any way to specify which input characters are accepted? (one could imagine the same idea would be useful for alpha-numeric only, etc.)

[gwenn]

Currently, you can't easily.
You can only reject final user input with a Validator.
An ugly and partial solution would be to rebind all ascii characters (except numeric and control) to Noop (no Beep/Bell command).

[gwenn]

Fixed in version 8.0.0
See https://github.com/kkawakam/rustyline/blob/master/examples/numeric_input.rs