About this package

This package contains extensions that you may find useful in your projects. Developers familiar with the Kotlin language will find many familiar things for themselves, since the package contains many methods from this language and not only­čśŐ Flutter extensions will be added in next versions.

Contributing

Please, consider contributing­čĹŹ

  • Add new feature
  • Fix a bug
  • Participate in discussions
  • Provide documentation
  • Create pull request

Dart

Custom classes

Pair

final Pair<int, int> x = Pair(2, 2);

Bool extensions

.not()

if(email.isEmpty.not()){
  checkEmailIsValid(email);
}

.and()

if(isEmailValid.and(isPasswordValid)){
  register(email, password);
}

.or()

if(hasGoodMarks.or(hasBenefits)){
  // Action()
}

Object extensions

Logging

Just use indside your custom class methods

logInfo(String message, [dynamic error]);
// or
logError(String message, [dynamic error]);
// or
logDebug(String message, [dynamic error]);
// or
logWarning(String message, [dynamic error]);
// or
logWtf(String message, [dynamic error]);

Scope functions

final String? nullableString = null;

nullableString?.let((it) {
    // Do something if string isn't null
});
final List<int> list = [1, 2, 3];

list.also((self) => print('List length ${self.length}'));

Iterable extensions

.elementAtOrNull()

final List<int> numbers = [1, 2, 3, 4, 5];

numbers.elementAtOrNull(numbers.length) // null

.find()

final List<int> numbers = [1, 2, 3, 4, 5];

numbers.find((e) => e >= 3) // 3

.getRandom()

final List<int> numbers = [1, 2, 3, 4, 5];

numbers.getRandom() // returns number from 1 to 5 

.zip()

final List<int> firstList = [1, 2, 3];
final List<double> secondList = [1.0, 2.0, 3.0];

final List<Pair<int, double>> zipRes = firstList.zip(secondList).toList(); 

.mapIndexed()

final List<int> firstList = [1, 2, 3, 4, 5];
final List<int> secondList = [1, 2, 3, 4, 5];

firstList.mapIndexed((index, item) => item + secondList[index]);

.filter()

final List<Person> people = [Person('John', 14), Person('Max', 22)];

people.filter((e) => e.age > 18); // [Person('Max', 22)]

.filterNot()

final List<Person> people = [Person('John', 14), Person('Max', 22)];

people.filterNot((e) => e.age > 18); // [Person('John', 14)]

.filterNotNull()

final List<Person?> people = [Person('John', 14), null, Person('Max', 22)];

people.filterNotNull(); // [Person('John', 14), Person('Max', 22)]

.forEachIndexed()

final List<int> numbers = [1, 2, 3, 4, 5];

numbers.forEachIndexed((index, item) => print(index)});

List extensions

.plus()

final List<int> numbers = [1, 2, 3];

numbers.plus(1); // [2, 3, 4]

.minus()

final List<int> numbers = [1, 2, 3];

numbers.minus(1); // [0, 1, 2]

.multiply()

final List<int> numbers = [1, 2, 3];

numbers.multiply(2); // [2, 4, 6]

.divide()

Only available for list of doubles

final List<double> numbers = [2.0, 4.0, 3.0];

numbers.divide(2); // [1.0, 2.0, 1.5]

Full list of extensions

Custom classes

  • Pair

Bool extensions

  • .not()
  • .and(other)
  • .or(other)

Object extensions

Logging

  • logInfo(message, [error])
  • logError(message, [error])
  • logDebug(message, [error])
  • logWarning(message, [error])
  • logWtf(message, [error])

Scope functions

  • .let()
  • .also()

Iterable extensions

  • .elementAtOrNull(index)
  • .find(predicate)
  • .getRandom()
  • .zip(collection)
  • .mapIndexed()
  • .forEachIndexed()
  • .filter(predicate)
  • .filterNot(predicate)
  • .filterNotNull()

List extensions

  • .plus(number)
  • .minus(number)
  • .multiply(number)
  • .divide(number)

String extensions

  • .isNullOrEmpty
  • .isNotBlank
  • .last
  • .isAlphabetOnly()
  • .isEmailValid([pattern])
  • .isPasswordLengthLonger()
  • .anyChar(predicate)
  • .toInt()
  • .toIntOrNull()
  • .toDouble()
  • .toDoubleOrNull()
  • .capitalizeFirst()
  • .removeAllWhiteSpace()
  • .reversed()
  • .replaceAfter(delimiter, replacement, [defaultValue])
  • .replaceBefore(delimiter, replacement, [defaultValue])

DateTime extensions

  • .isToday
  • .isYesterday
  • .isTomorrow
  • .date
  • .isSameDay(dateTime)
  • .isAtSameYearAs(dateTime)
  • .isAtSameMonthAs(dateTime)
  • .isAtSameDayAs(dateTime)
  • .isAtSameHourAs(dateTime)
  • .isAtSameMinuteAs(dateTime)
  • .isAtSameSecondAs(dateTime)
  • .copyWith(year, month, day, hour, minute, second, millisecond, microsecond)
  • .min(dateTime)
  • .max(dateTime)
  • .differenceInDays(dateTime)
  • .differenceInHours(dateTime)
  • .differenceInMinutes(dateTime)
  • .differenceInSeconds(dateTime)

Libraries

useful_extensions