# askNumber

[Built-ins](README.md)

Canonical ID: `input.readNumber`. Nederlands: `vraagGetal`.

Asks for a number between the minimum and maximum and returns a `Number`.

**Inclusive bounds** include the endpoints: a minimum of 1 and maximum of 5 allow 1 and 5 too. **Finite** excludes infinity and invalid numeric values. **Trimming whitespace** removes spaces and similar characters at the start and end. **Normalizing** changes an accepted spelling to one agreed form, such as the reply `"2,5"` becoming `2.5`.

**Exponent notation** in a number reply, such as `1e2`, means one times ten to the power two: 100. A sign is `+` or `-`. These are rules for answering a question; they do not make `1e2` a valid Pliro source-number literal. A particular input box may restrict what you can type.

The input flow handles invalid replies before returning a value.

## Signature

```text
askNumber(prompt, minimum, maximum)
```

## Arguments

| Parameter | Type | Requirement |
|---|---|---|
| `prompt` | Text | Question displayed by the host. |
| `minimum` | Number | Finite inclusive lower bound, no greater than maximum. |
| `maximum` | Number | Finite inclusive upper bound. |

## Return value

`Number`.

## Example

```pliro
# language: en
let level = askNumber("Level: 1-5", 1, 5)
say level * 10
```

Entering `3` prints `30`.

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