CTRL-P/CTRL-N unexpected behavior

[doug-moen]

CTRL-P and CTRL-N do not work as expected in the head revision.
What they should do is move up and down the history list, just like up-arrow and down-arrow.
They used to work this way, but the behaviour has changed.

Can reproduce using the example application.

[doug-moen]

The problem with this new behaviour is that it conflicts with the defacto standard for how CTRL-P and CTRL-N work in all other apps that I've tested: eg, the bash shell, the python shell, etc. I guess what I want is readline compatibility with no surprises for my users.

If you type CTRL-P on an empty line, instead of getting the previous history item, as expected, you get the last identifier in the completion list, which isn't useful in this context.

I found the following code:

    bind_key( Replxx::KEY::control( 'N' ),                 _namedActions.at( action_names::COMPLETE_NEXT ) );
    bind_key( Replxx::KEY::control( 'P' ),                 _namedActions.at( action_names::COMPLETE_PREVIOUS ) );

I guess the new behaviour is deliberate.

The above code conflicts with the comments in this code:

// ctrl-N, recall next line in history
Replxx::ACTION_RESULT Replxx::ReplxxImpl::history_next( char32_t ) {
       return ( history_move( false ) );
}
// ctrl-P, recall previous line in history
Replxx::ACTION_RESULT Replxx::ReplxxImpl::history_previous( char32_t ) {
      return ( history_move( true ) );
}

[AmokHuginnsson]

Hi @doug-moen

Yes. In fact CTRL-P and CTRL-N mappings were deliberately changed from readline's defaults.
The old behavior can be brought back in client application by adding

bind_key_internal( Replxx::KEY::control( 'N' ), "history_next" );
bind_key_internal( Replxx::KEY::control( 'P' ), "history_previous" );

lines.

The discussion wether changing the default was a good decision in the long term would be interesting
but possibly off-topic at the same time.

I hope that new API that replxx provides makes it easy for every client to get back to old behavior.

[AmokHuginnsson]

Sorry, for closing this issue, that was a miss-click.

[doug-moen]

You may have changed other key bindings to be different from readline, or you may decide to make additional changes in the future.

What would help me is a standard function to reset the key bindings to be readine compatible:

void Replxx::use_readline_key_bindings()

Would you consider adding this function?

[AmokHuginnsson]

replxx could read configuration file in the vein of .inputrc.
This configuration file could contain this kind of bash-compatible settings.
I would accept pull request implementing this kind of feature for replxx,
I mean loading replxx initialization file (could be loaded from ${HOME}/.replxxrc by default or from an explicit path).

Personally I will work on adding support for 256 color palette to replxx first.