Prompt

Time for a little example of a simple thing you can use Term.jl for: asking for some input. Use a Prompt, ask a question, get an answer. Simple, but a little extra style. That's what AbstractPrompt types are for. There's a few different flavors, which we'll look at in due time, but essentially a prompt is made of a bit of text, the prompt that is displayed to the user, and some machinery to capture the user's input and parse it/ validate it.

For example:

using Term.Prompts

prompt = Prompt("Simple, right?");

╭───────────────────────────────────╮
│   prompt::String Simple, right?   │
│   style::String     #42A5F5       │
│                                   │
╰─────────── Term.Prompts.Prompt ───╯

creates a Prompt object and ask then prints the prompt and asks for input:

prompt |> ask

the output should look something like

❯❯❯ Simple, right?

here we construct a basic Prompt and "ask" it: print the message and capture the reply. ask returns the answer, which you can do with as you please. A small warning before we carry on:

Prompt flavours

There's a couple more ways you can use prompts like. One is to ensure you get an answer of the correct Type, using the imaginatively names TypePrompt:

# this only accepts `Int`s
prompt = TypePrompt(Int, "give me a number")  # don't forget to |> ask

❯❯❯ give me a number

If your answer can't be converted to the correct type you'll get a AnswerValidationError, not good.

So, what if you want to get user inputs, but you don't want to handle any crazy input they can provide? Fear not, use OptionsPrompt so that only acceptable options will be ok. This will keep "asking" your prompt until the user's answer matches one of the given options

prompt = OptionsPrompt(["a lot", "so much", "the most"], "How likely would you be to recommend Term.jl to a friend or colleague?") # don't forget to |> ask

❯❯❯ How likely would you be to recommend Term.jl to a friend or colleague?
  a lot / so much / the most

Okay, so much typing though. Let's be realistic, most likely you just want to ask a yes/no question and the answer is likely just yes. So just use a DefaultPrompt:

# one says the first option is the default
prompt = DefaultPrompt(["yes", "no"], 1, "Confirm?") # don't forget to |> ask

❯❯❯ Confirm?
  yes, no

still too much typing? You can just use the confirm function which is equivalent to asking the prompt shown above.

Style

The style of prompt elements (e.g. the color of the prompt's text or of the options) is defined in Theme. You can also pass style information during prompt creation:

Prompt("Do you like this color?", "red") |> println
DefaultPrompt(["yes", "no"], 1, "Confirm?", "green", "blue", "red") |> println

❯❯❯ Do you like this color?

❯❯❯ Confirm?
  yes, no