# Dart Decimals

This project enable to make computations on decimal numbers without losing precision like double operations.

For instance :

``````// with double
print(0.2 + 0.1); // displays 0.30000000000000004

// with decimal
print(Decimal.parse('0.2') + Decimal.parse('0.1')); // displays 0.3
``````

## Usage

To use this library in your code :

• add a dependency in your `pubspec.yaml` :
``````dependencies:
decimal:
``````
• add import in your `dart` code :
``````import 'package:decimal/decimal.dart';
``````
• Start computing using `Decimal.parse('1.23')`.

Hint : To make your code shorter you can define a shortcut for Decimal.parse :

``````final d = (String s) => Decimal.parse(s);
d('0.2') + d('0.1'); // => 0.3
``````

## Formatting with intl

You can use the intl package to format decimal with `DecimalFormat` from the `package:decimal/intl.dart` library:

``````import 'package:decimal/decimal.dart';
import 'package:decimal/intl.dart';

main() {
var value = Decimal.parse('1234.56');
var formatter = DecimalFormatter(NumberFormat.decimalPattern('en-US'));
print(formatter.format(value));
}
``````

Tip: you can define an extension to make it more fluent:

``````extension on Decimal {
String formatWith(NumberFormat formatter) => formatter.format(DecimalIntl(this));
}
main() {
var value = Decimal.parse('1234.56');
var formatter = DecimalFormatter(NumberFormat.decimalPattern('en-US'));
print(value.formatWith(formatter));
}
``````

WARNING: For now (2024.05.30) intl doesn't work with `NumberFormat.maximumFractionDigits` greater than 15 on web plateform and 18 otherwise.

## Parsing with intl

You can use the `NumberFormat` from intl package to parse formatted decimals

``````var currencyFormatter = DecimalFormatter(NumberFormat.simpleCurrency(name: 'USD'));
currencyFormatter.parse('\\$3.14'); // => 3.14
``````