lmorg/readline

Import Path

From CLI:

go get github.com/lmorg/readline/v4

From Go code:

import "github.com/lmorg/readline/v4"

Preface

This package provides the interactive capabilities for various command line interfaces such as the shell Murex.

It also has experimental support for handling text input operations in GUI applications. However its primary focus is as a "batteries included" CLI input library.

readline In Action

This is a very rough and ready recording but it does demonstrate a few of the features available in readline. These features include:

• hint text (the blue status text below the prompt - however the colour is configurable)
• syntax highlighting (albeit there isn't much syntax to highlight in the example)
• tab-completion in gridded mode (seen when typing cd)
• tab-completion in list view (seen when selecting an process name to kill and the process ID was substituted when selected)
• regex searching through the tab-completion suggestions (seen in both cd and kill - enabled by pressing [CTRL+f])
• line editing using $EDITOR (vi in the example - enabled by pressing [ESC] followed by [v])
• readline's warning before pasting multiple lines of data into the buffer
• the preview option that's available as part of the aforementioned warning
• and VIM keys (enabled by pressing [ESC])

Example Code

Using readline is as simple as:

func main() {
    rl := readline.NewInstance()

    for {
        line, err := rl.Readline()

        if err != nil {
            fmt.Println("Error:", err)
            return
        }

        fmt.Printf("You just typed: '%s'\n", line)
    }
}

However I suggest you read through the examples in /examples for help using some of the more advanced features in readline.

The source for readline will also be documented in godoc: https://godoc.org/github.com/lmorg/readline/v4

Version Information

Because the last thing a developer wants is to do is fix breaking changes after updating modules, I will make the following guarantees:

• The version string will be based on Semantic Versioning. ie version numbers will be formatted (major).(minor).(patch) - for example 2.0.1

• major releases will have breaking changes. Be sure to read CHANGES.md for upgrade instructions

• minor releases will contain new APIs or introduce new user facing features which may affect useability from an end user perspective. However minor releases will not break backwards compatibility at the source code level and nor will it break existing expected user-facing behavior. These changes will be documented in CHANGES.md too

• patch releases will be bug fixes and such like. Where the code has changed but both API endpoints and user experience will remain the same (except where expected user experience was broken due to a bug, then that would be bumped to either a minor or major depending on the significance of the bug and the significance of the change to the user experience)

• Any updates to documentation, comments within code or the example code will not result in a version bump because they will not affect the output of the go compiler. However if this concerns you then I recommend pinning your project to the git commit hash rather than a patch release

My recommendation is to pin to either the minor or patch release and I will endeavour to keep breaking changes to an absolute minimum.

Hotkeys

readline hotkeys can be found in Murex's documentation. While some of that document will be specific to Murex, the vast majority of Murex's interactive capabilities is leveraged via this readline package.

Change Log

The full changelog can be viewed at CHANGELOG.md

License Information

readline is licensed Apache 2.0. All the example code and documentation in /examples is public domain.