Prompts

Table of Contents

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• Table of Contents
• Prompt handlers
• Logging to the shell
  • Transient log
  • Classic prompt log
  • Demo

Readline supports most of the prompts offered by Oh-My-Posh, namely:

• $PS1 - the primary prompt.
• $PS2 - the secondary prompt.
• RPROMPT - The right prompt, (which is not to be confused with a right-aligned primary prompt)
• Tooltip - A prompt being refreshed at every key input in the line (check [here] for an example).
• Transient - A prompt being printed in place of PS1 after command/line execution.

Additionally, readline supports those prompts for any valid oh-my-posh configuration.

Prompt handlers

The following functions are available to bind prompt handlers.

func (p *prompt) Primary(prompt func() string)
func (p *prompt) Right(prompt func() string)
func (p *prompt) Secondary(prompt func() string)
func (p *prompt) Transient(prompt func() string)
func (p *prompt) Tooltip(prompt func(tip string) string)

An extract of the console library previously mentioned above uses them like this:

func (prompt *Prompt) bind(shell *readline.Instance) {
    
    // The oh-my-posh prompt engine, with a loaded configuration. 
    p := prompt.Engine
        
    shell.Prompt.Primary(p.PrintPrimary)
    shell.Prompt.Right(p.PrintRPrompt)

    // Secondary prompt.
    secondary := func() string {
        return p.PrintExtraPrompt(engine.Secondary)
    }
    shell.Prompt.Secondary(secondary)

    // Transient prompt (never nil, but enabled with the readline configuration file)
    transient := func() string {
        return p.PrintExtraPrompt(engine.Transient)
    }
    shell.Prompt.Transient(transient)

    shell.Prompt.Tooltip(p.PrintTooltip)
}

Logging to the shell

The shell offers two methods to print output with different behavior.

Transient log

The first method will actually "push" the prompt below a log line to be printed. In detail, the current prompt/line/helpers are cleared, the log output is printed, and the prompt/line is redisplayed below it.

func (rl *Instance) LogTransient(msg string, args ...interface{})

Classic prompt log

There may be some cases, though, where you want the current prompt to be left as is, your log event to be printed below it, and a new prompt/input line to be displayed below. For this, the following method is given:

func (rl *Instance) Log(msg string, args ...interface{})

Demo

The following shows a ticker printing 6 notification messages: the first 5 with the LogTransient() function, and the last one with Log().