# askYesNo

[Built-ins](README.md)

Canonical ID: `input.readBoolean`. Nederlands: `vraagJaNee`.

Asks a yes/no question and returns a Boolean. Graphical hosts provide bounded choices. Console replies accept true/yes/y/waar/ja/j/1 and false/no/n/onwaar/nee/0, ignoring letter case and surrounding whitespace. Use the Boolean directly in a condition instead of comparing it with text.

## Signature

```text
askYesNo(prompt)
```

## Arguments

| Parameter | Type | Requirement |
|---|---|---|
| `prompt` | Text | Question displayed by the host. |

## Return value

`Boolean`.

## Example

```pliro
# language: en
let ready = askYesNo("Start?")
if ready:
    say "A"
else:
    say "B"
```

Yes selects `A`; no selects `B`.

## Notes and common mistakes

Use the function name for your source language. Its [canonical ID](../concepts/canonical-identity.md) is a shared documentation label; you do not type that ID as a call. Giving your own variable or function the same name can hide the built-in. Supply the documented [arguments](../concepts/parameters-and-arguments.md) and value types. Pliro reports mismatches when checking can detect them, or when the call runs.

The selected host mediates input. Program replies are bounded to 64 KiB of valid [UTF-8](../concepts/utf-8.md); unavailable input produces E4010. Keyboard names and option strings are data and are not translated with source syntax. Completed prompts are cooperative checkpoints.

## Related entries

[ask](ask.md) · [askNumber](askNumber.md) · [choose](choose.md) · [keyDown](keyDown.md) · [Programming guides](../guides/input.md) · [Host support](../guides/hosts.md) · [Calls and arguments](../syntax/calls.md)