# Terminal & Prompting
Let's say we want to ask the user for confirmation whenever they run the `goodbye` command by a sincere
please telling us not to. We can achieve this using the `Terminal`, a collection of interactive terminal utilities.
## Confirmation
![confirm prompt asking 'do you want to go out with me [Y/y]' responded 'hell no'](../images/do_you_want_to_go_out with_me__[Y_y]__hell_no.png)
We can ask the user for confirmation with the `Confirm` builder pattern like so:
```rust
// use vecli::*;
// ...
Confirm::new("Are you sure you want to say goodbye?").ask();
// or alternatively: Terminal::confirm("Are you sure you want to say goodbye?")
```
This will show a prompt confirming the user about the given prompt, and returns the user's answer as a boolean (yes being true and no otherwise).
By default, Confirm has the default (when the user doesn't give a value) value of `false`. We can change this by configuring the Confirm builder.
### Configuring Confirmation
There's a measly two configuration options for `Confirm`, which is:
* **`.default(b)`**: `false` by default, changes the default choice to the given boolean.
* **`.show_default(b)`**: `true` by default, and if false, will not show the default option beside the prompt.
And if you chose to do it using the manual `Terminal::confirm()` command, here's the order of parameters:
```rust
prompt: &str,
default: Option<bool>,
show_default: Option<bool>,
```
Notice `Option` is being used. You'll have to manually wrap the boolean in `Some()`, this is why the builder (`Confirm`)
is much appreciated.
### What It Looks Like
Put the code block above on our previous `goodbye` command, print "Aborted" and return if it evaluates to true.
Running the app with `cargo run hello goodbye` should result in the following:
```sh
$ cargo run hello goodbye
Are you sure you want to say goodbye? [y/N]: y
Hello!
Goodbye!
$ cargo run hello goodbye
Are you sure you want to say goodbye? [y/N]: n # or just enter without giving a value
Aborted
```
## Prompting
Okay, let's get to inputs. We want `hello` to also ask for the name to be displayed, but `Confirm` wouldn't cut it because it's only yes or no.
Well, it *would*, but that would mean spending a bunch of confirm prompts for a finite amount of names. That's just... bad.
We can solve the problem by using `Terminal::prompt()`.
Consider the following:
```rust
// ...
Terminal::prompt("Who do you want to greet?");
```
Notice we don't use spaces at the end, it's because `prompt` automatically suffixes them.
The code block above would return a `String` of whatever the user responds with.
## Choices
For some reason, let's add a new command that asks the user for their favorite fruit.
Add the command [like mentioned before](../core-concepts/commands.md), and we want to give a hard-coded choice of what you think are the best fruit nominees.
> [!NOTE]
> Subjective opinion alert. If you can't handle them, then boohoo.
Now for what I think are the nominees for 'best fruit' are mangoes, watermelons, grapes, and oranges. Maybe I forgot some, I don't know. Submit an issue to the repo or something.
> [!NOTE]
> Like I'd change a page just because of the issue '[insert fruit here] not included in docs'...
We can easily do the task with the `Choice` builder (alternatively the `Terminal::choice()` command):
```rust
// ...
Choice::new("What's the best fruit?", ["mango", "watermelon", "grape", "orange"]).ask();
```
The code above will return the `String` of whatever the user chose.
### Configuring Choices
Let's say you like a fruit on the list so bad, you want to make it the default. Well worry not, there's actually some configuration options for that and more.
* **`.default(&str)`**: Makes the default option the passed `&str`. Panics if the passed argument isn't in one of the options.
* **`.show_default(bool)`**: `true` by default. If true, shows the default value by marking it with an asterisk (`*`). Else, don't mark it.
* **`.show_choices(bool)`**: `true` by default. If false, not show any choices at all. Not recommended unless you intend to have a choice-showing interface of your own.
### The Code
Let's use the `"mango"` option as an example. The full block would be:
```rust
// ...
Choice::new("What's the best fruit?", ["mango", "watermelon", "grape", "orange"])
.default("mango")
.show_default(true) // default is true anyway,
.show_choices(true) // but just for the sake of showing.
```
A few possibilities for this feature could be a quiz of some sort. I don't know, make something awesome with vecli!
---
If you've been this far from the beginning, congrats! This doc is under production and you've reached the end... for now. More guides will be added soon! For now, read the API reference at [docs.rs](https://docs.rs/vecli).