The dart_helper_utils package provides a collection of Dart utilities, tools for converting dynamic objects to various types, and extending core Dart classes with extension.

Note: This package is tailored for Dart projects. For Flutter projects, use flutter_helper_utils, which includes all dart_helper_utils features plus additional utilities and extension for Flutter, such as Widget, Color, and BuildContext extension.

Table of Contents #

Featured
- Converting Objects
- TimeUtils
Extensions

Featured #

Converting Objects #

Convert objects to various types, such as int, double, bool, String, List, Set, and Map. These methods are useful when dealing with dynamic data from APIs, offering simple and flexible type conversions.

Sample Usage: #

Given an API response:


Map<String, dynamic> apiResponse = {'score': '12.4'};

// Using parse
int score = double.parse(apiResponse['score']).toInt();

// Using the package:
int score = toInt(apiResponse['score']);

Available Conversions: #

Methods:

toNum() / tryToNum()
toInt() / tryToInt()
toDouble() / tryToDouble()
toBool() / tryToBool()
toString1() / tryToString()
toList<T>() / tryToList<T>()
toSet<T>() / tryToSet<T>()
toMap<K, V>() / tryToMap<K, V>()

Static Methods: #

The methods above call the original static methods from the ConvertObject class. For instance:

int score = toInt(map['key']); // global method
// same as
int score = ConvertObject.toInt(map['key']); // static method

Note: To avoid conflicts with method names (e.g., toList), use the static method directly:

List myList = ConvertObject.toList(dynamicObject);

Optional Parameters: #

Each method accepts two optional parameters: listIndex and mapKey. These parameters allow specific value extraction and conversion within a List or Map.
All dates and number conversion methods accepts extra format, and local for better localization and formatting.

Example with `listIndex`:

dynamic dynamicList = ['10', '20', '30'];
final int number = toInt(dynamicList, listIndex: 1); // 20

Example with `mapKey`:

final dynamicMap = <dynamic, dynamic>{
  'name': 'John',
  'age': '30',
  'bools': {
    'isHuman': 'yes',
  }
};
final bool isHuman = toBool(dynamicMap['bools'], mapKey: 'isHuman'); // true

Auto Decoding of JSON Strings for Collections

The ConvertObject class now simplifies working with JSON data by automatically decoding raw JSON strings when converting to List, Set, or Map types. This eliminates the need for manual parsing before conversion.

Example Usage:

final myList = tryToList<int>("[1, 2, 3]"); // List<int>
final mySet = tryToSet<String>('["hello", "world"]'); // Set<String>
final myMap = tryToMap<String, dynamic>('{"name": "Alice", "age": 30}'); // Map<String, dynamic>

Extract And Convert #

Starting from version 2.0.0 and above, we added a new methods to easily extract values from Map<K, V> and List<E>, and, safely convert it to a specific type!

getString, getNum, getInt, getBigInt, getDouble, getBool, getDateTime, getUri, getMap, getSet, and getList.
For Map, it requires the key e.g. map.getNum('key')
For List, it requires the index e.g. list.getNum(1)
They also supports nullable converters such as tryGetString, tryGetNum, tryGetInt, etc.
all supported types and optionals in the ConvertObject class are also included.

Sample:

final map = <dynamic, dynamic>{
  'name': 'John',
  'age': '30',
  'bools': {
    'isHuman': 'yes',
  }
};

final age = map.getInt('age'); // 30
final score = map.tryGetInt('score'); // null
final isHuman = map.getBool('bools', innerKey: 'isHuman'); // true

or with List:

final dynamicList = <dynamic>['John', 30, true];
final age = dynamicList.getInt(1); // 30

TimeUtils: #

The TimeUtils class provides utilities for measuring and comparing execution times, creating throttled functions, running tasks periodically, and handling tasks with timeouts. Here is a sample with the executionDuration method:

final excutionTime = await TimeUtils.executionDuration(() {
  for (var i = 0; i < 1000000; i++) {}
});
print('Synchronous task took $syncDuration');
// NOTE: works also with asynchronous task

Another example with runWithTimeout:

try {
  final result = await TimeUtils.runWithTimeout(
    task: () async {
      await 5.secDelay;
      return 'Completed';
    },
    timeout: const Duration(seconds: 3),
  );
  print('Result: $result');
} catch (e) {
  print('Error: $e');
}

Extensions #

Date Extensions #

Parsing #

timestampToDate: Converts a timestamp (milliseconds since epoch) to a DateTime object.
try/toDateTime: Converts a string to a DateTime object.

Formatting #

local: Converts a potentially null DateTime to local time.
toUtcIso: Converts a potentially null DateTime to ISO 8601 format in UTC.
format: Formats a DateTime object into a string according to the given format.

Comparison #

Relative to Current Time:
- isTomorrow
- isToday
- isYesterday
- isInFuture
- isInPast
- isInPastWeek
- isInThisYear
Within the Month/Year:
- isFirstDayOfMonth
- isLastDayOfMonth
- isLeapYear
Component-Level: (Compare two DateTime objects)
- isAtSameYearAs(other: DateTime)
- isAtSameMonthAs(other: DateTime)
- isAtSameDayAs(other: DateTime)
- ... (and so on for hour, minute, etc.)

Duration Calculation #

passedDuration: Gets the duration that has passed since the given (potentially null) DateTime.
remainingDuration: Gets the duration remaining until the given (potentially null) DateTime.
passedDays: Gets the number of days that have passed since the given (potentially null) DateTime.
remainingDays: Gets the number of days remaining until the given (potentially null) DateTime.

Manipulation #

Start Points:
- startOfDay: Gets the start of the day (midnight) for the given DateTime.
- startOfMonth: Gets the start of the month for the given DateTime.
- startOfYear: Gets the start of the year for the given DateTime.
Extraction:
- dateOnly: Extracts only the date portion (midnight time) from the DateTime.
Lists:
- daysInMonth: Gets a list of all the DateTime objects representing the days in the month of the given DateTime.
Navigation:
- previousDay, nextDay: Gets the DateTime for the previous/next day.
- previousWeek, nextWeek: Gets the DateTime for the previous/next week.
- firstDayOfWeek, lastDayOfWeek: Gets the DateTime for the first/last day of the week.
- previousMonth, nextMonth: Gets the DateTime for the previous/next month.
- firstDayOfMonth, lastDayOfMonth: Gets the DateTime for the first/last day of the month.

Extensions For Intl #

DateFormat #

on String

dateFormat: Returns a DateFormat object based on the string pattern.
try/toDateAutoFormat: Parses the string to DateTime and autodetect the format, with the provided locale, useCurrentLocale, and UTC option.
try/toDateFormatted: Parses the string to DateTime with the provided format, locale, and UTC option.
try/toDateFormattedLoose: Parses the string to DateTime using loose parsing.
try/toDateFormattedStrict: Parses the string to DateTime using strict parsing.
try/toDateFormattedUtc: Parses the string to DateTime in UTC using the provided format and locale.
localeExists: Checks if the locale exists in DateFormat.

on DateTime

tryFormat and format: Formats the DateTime object using the provided pattern and optional locale.
A variety of methods to format DateTime objects in different styles:
- Basic: yMMMMdFormat, formatAsd
- Weekday: formatAsEEEE, formatAsEEEEE
- Month: formatAsLLL, formatAsLLLL, formatAsMMMMEEEEd, etc.
- Quarter: formatAsQQQ, formatAsQQQQ
- Year: formatAsyMMM, formatAsyQQQQ, etc.
- Time: formatAsH, formatAsHm, etc. All methods support an optional locale parameter.

NumberFormat #

on String

numberFormat: Returns a NumberFormat object based on the string pattern.
try/toNumFormatted: Parses the string to a number with the given pattern and locale.
try/toIntFormatted: Parses the string to an integer with the given pattern and locale.
try/toDoubleFormatted: Parses the string to a double with the given pattern and locale.
numberFormat: Creates a NumberFormat object using the string as the pattern, along with the given locale.
symbolCurrencyFormat: Creates a NumberFormat object as currency using the string as the currency symbol, along with the given locale and optional decimal digits.
simpleCurrencyFormat: Creates a NumberFormat object as simple currency using the string as the currency name, along with the given locale.
compactCurrencyFormat: Creates a NumberFormat object as compact simple currency using the string as the currency name, along with the given locale.

on Num

formatAsCurrency: Formats the number as currency with the given locale, symbol, and decimal digits.
formatAsSimpleCurrency: Formats the number as simple currency with the given locale and name.
formatAsCompact: Formats the number in a compact form with the given locale.
formatAsCompactLong: Formats the number in a long compact form with the given locale.
formatAsCompactCurrency: Formats the number as compact simple currency with the given locale and name.
formatAsDecimal: Formats the number as a decimal with the given locale and decimal digits.
formatAsPercentage: Formats the number as a percentage with the given locale.
formatAsDecimalPercent: Formats the number as a decimal percentage with the given locale and decimal digits.
formatAsScientific: Formats the number as a scientific value with the given locale.
formatWithCustomPattern: Formats the number using a custom pattern with the given locale.

General #

on Map

intlSelectLogic: Selects a value from the map based on a choice.
intlSelect: Formats a message based on the choice and returns the formatted message.

on Num

pluralize: Returns a localized string based on the plural category of the number.
getPluralCategory: Determines the plural category of the number based on the current locale.

on String

setAsDefaultLocale: Sets the string as the default locale for subsequent Intl operations.
setAsSystemLocale: Sets the string as the system locale.
translate: Translates the string using Intl.message.
genderSelect: Selects a localized string based on the gender associated with the string.
getGenderCategory: Determines the gender category of the string based on the current locale.

TextDirection #

These constants eliminate the need to import and use the TextDirection class from the intl package, which could be confused with Flutter's TextDirection enum.

textDirectionLTR: Represents left-to-right text direction (e.g., English, French).
textDirectionRTL: Represents right-to-left text direction (e.g., Arabic, Hebrew).
textDirectionUNKNOWN: Represents unknown or neutral text direction.

Bidi #

on TextDirection

toBidiFormatter: Creates a BidiFormatter object based on the directionality.

on String

stripHtmlIfNeeded: Strips HTML tags from the string if needed, preserving bidirectional text direction.
startsWithLtr: Checks if the string starts with left-to-right (LTR) text, optionally considering HTML markup.
startsWithRtl: Checks if the string starts with right-to-left (RTL) text, optionally considering HTML markup.
endsWithLtr: Checks if the string ends with left-to-right (LTR) text, optionally considering HTML markup.
endsWithRtl: Checks if the string ends with right-to-left (RTL) text, optionally considering HTML markup.
hasAnyLtr: Checks if the string contains any left-to-right (LTR) characters, optionally considering HTML markup.
hasAnyRtl: Checks if the string contains any right-to-left (RTL) characters, optionally considering HTML markup.
isRtlLanguage: Checks if the string represents a right-to-left (RTL) language text.
enforceRtlInHtml: Enforces right-to-left (RTL) directionality in HTML markup.
enforceRtlIn: Enforces right-to-left (RTL) directionality in plain text.
enforceLtrInHtml: Enforces left-to-right (LTR) directionality in HTML markup.
enforceLtr: Enforces left-to-right (LTR) directionality in plain text.
guardBracketInHtml: Guards brackets in HTML markup to maintain bidirectional text support.
guardBracket: Guards brackets in plain text to maintain bidirectional text support.
guessDirection: Guesses the text directionality based on its content, optionally considering HTML markup.
detectRtlDirectionality: Detects the predominant text directionality in the string, optionally considering HTML markup.
wrapWithSpan: Wraps the text with a span tag and sets the direction attribute (dir) based on the provided or estimated direction.
wrapWithUnicode: Wraps the text with unicode BiDi formatting characters based on the provided or estimated direction.

String Extension #

Case Conversion #

toPascalCase: PascalCase aka (UpperCamelCase).
toTitleCase: Title Case
toCamelCase: camelCase aka (dromedaryCase)
toSnakeCase: snake_case aka (snail_case, pothole_case).
toKebabCase: kebab-case aka (dash-case, lisp-case, spinal-case).
toScreamingSnakeCase: SCREAMING_SNAKE_CASE aka (MACRO_CASE, CONSTANT_CASE, ALL_CAPS).
toScreamingKebabCase: SCREAMING-KEBAB-CASE aka (COBOL-CASE).
toPascalSnakeCase: Pascal_Snake_Case.
toPascalKebabCase: Pascal-Kebab-Case.
toTrainCase: Train-Case aka (HTTP-Header-Case).
toCamelSnakeCase: camel_Snake_Case.
toCamelKebabCase: camel-Kebab-Case.
toDotCase: dot.case.
toFlatCase: flatcase.
toScreamingCase: SCREAMINGCASE.
toTitle: Capitalizes the first letter of each word in the string while retaining -, _, and space characters.
toWords: Converts any String to a List<String>, handling complex cases more effectively than the native split() method.

Text Formatting #

lowercaseFirstLetter: Lowercases only the first letter of the string, preserving the rest of the case.
capitalizeFirstLetter: Converts the first letter to uppercase and preserves the rest of the case.
capitalizeFirstLowerRest: Converts the first letter to uppercase and the rest to lowercase.
tryToLowerCase: Converts the string to lowercase if it's not null.
tryToUpperCase: Converts the string to uppercase if it's not null.
removeEmptyLines: Removes consecutive empty lines, replacing them with single newlines.
toOneLine: Converts to a single line by replacing all newline characters with spaces.
removeWhiteSpaces: Removes all whitespace characters.
clean: Combines removeWhiteSpaces and toOneLine to collapse into a single line.
wrapString: Wraps text based on the specified word count, wrapping behavior, and custom delimiter.

String Replacement #

replaceAfter: Replaces part of the string after the first occurrence of the given delimiter with a specified string.
replaceBefore: Replaces part of the string before the first occurrence of the given delimiter with a specified string.
removeSurrounding: Removes the surrounding delimiter if it exists at both ends.

String Comparison #

equalsIgnoreCase: Compares with another string for equality, ignoring case differences.

String Limiting #

limitFromEnd: Shrinks the string to no more than a specified length, starting from the end.
limitFromStart: Shrinks the string to no more than a specified length, starting from the start.

Character Checks #

isAlphanumeric: Checks if the string contains only letters and numbers.
hasSpecialChars: Checks if the string contains any characters that are not letters, numbers, or spaces.
hasNoSpecialChars: Checks if the string does not contain any special characters.
startsWithNumber: Checks if the string starts with a number.
containsDigits: Checks if the string contains any digits.
hasCapitalLetter: Checks if the string contains at least one capital letter.
isNumeric: Checks if the string consists only of numbers.
isAlphabet: Checks if the string consists only of alphabetic characters.
isBool: Checks if the string is a boolean value (true or false).

Validation #

isValidUsername: Checks if the string is a valid username.
isValidCurrency: Checks if the string is a valid currency format.
isValidPhoneNumber: Checks if the string is a valid phone number.
isValidEmail: Checks if the string is a valid email address.
isValidHTML: Checks if the string is a valid HTML file or URL.
isValidIp4: Checks if the string is a valid IPv4 address.
isValidIp6: Checks if the string is a valid IPv6 address.
isValidUrl: Checks if the string is a valid URL.
isEmptyOrNull || isBlank: Checks if the string is null or empty.
isNotEmptyOrNull || isNotBlank: Checks if the string is not null and not empty.
isPalindrome: Checks if the string is a palindrome.

Utility #

orEmpty: Returns the string if it is not null, or an empty string otherwise.
ifEmpty: Performs an action if the string is empty.
lastIndex: Gets the last character of the string.
isNotBlank: Returns true if the string is neither null, empty, nor solely made of whitespace characters.
toCharArray: Returns a list of characters.
insert: Inserts a specified string at a specified index position.
isNullOrWhiteSpace: Indicates whether the string is null, empty, or consists only of white-space characters.
asBool: Converts the string to a boolean.
decode/tryDecode: Decodes the JSON string into a dynamic data structure (tryDecode returns null upon failure).

Parsing #

try/toNum: Parses the string as a number.
try/toDouble: Parses the string as a double.
try/toInt: Parses the string as an integer.

Collection Extension #

Iterable Extension #

Type-safe extract and convert methods like getInt(index), getDateTime(index), getMap(index) etc.
isEmptyOrNull: Returns true if the iterable is either null or empty.
isNotEmptyOrNull: Returns false if the iterable is either null or empty.
of: Retrieves the element at the specified index in a null-safe manner.
firstOrNull: Retrieves the first element or returns null.
lastOrNull: Retrieves the last element or returns null.
firstWhereOrNull: Retrieves the first element that matches the specified predicate or returns null.
firstOrDefault: Retrieves the first element or returns a default value.
lastOrDefault: Retrieves the last element or returns a default value.
tryGetRandom: Retrieves a random element from the iterable or returns null.
orEmpty: Returns the iterable if it's not null and the empty list otherwise.
any: Returns true if at least one element matches the given predicate.
concatWithSingleList: Concatenates the current iterable with another iterable.
concatWithMultipleList: Concatenates the current iterable with multiple iterables.
toMutableSet: Converts the iterable to a set.
intersect: Returns a set containing all elements that are contained by both this set and the specified collection.
groupBy: Groups the elements by the value returned by the specified key function.
filter: Returns a list containing only elements matching the given predicate.
filterNot: Returns a list containing all elements not matching the given predicate.
mapList: Returns the result of applying a function to each element in the iterable as a list.
whereIndexed: Returns an iterable with all elements that satisfy the predicate.
forEachIndexed: Performs the given action on each element in the iterable, providing the sequential index with the element.
sortedDescending: Returns a new list with all elements sorted in descending order.
containsAll: Returns true if all elements in the specified collection are contained in this collection.
count: Returns the number of elements that match the given predicate.
all: Returns true if all elements match the given predicate.
distinctBy: Returns a new list containing the first occurrence of each element with a unique key, as determined by the provided key selector function.
subtract: Returns a set containing all elements that are contained by this collection and not contained by the specified collection.
find: Returns the first element matching the given predicate, or null if not found.
encodedJson: Encodes the iterable as a JSON string.

List Extension #

tryRemoveAt: Removes the element at the specified index in a null-safe manner.
indexOfOrNull: Retrieves the index of the specified element in a null-safe manner.
indexWhereOrNull: Retrieves the index of the first element that matches the specified predicate in a null-safe manner.
tryRemoveWhere: Removes elements that match the specified condition in a null-safe manner.
halfLength: Returns half the size of the list.
takeOnly: Returns a list containing the first n elements.
drop: Returns a list containing all elements except the first n elements.
firstHalf: Returns the first half of the list.
secondHalf: Returns the second half of the list.
swap: Returns a list with two items swapped.
getRandom: Retrieves a random element from the list.

Set Extension #

isEmptyOrNull: Checks if the set is empty or null.
isNotEmptyOrNull: Checks if the set is not empty or null.
addIfNotNull(T? value): Adds a value to the set if it's not null.
toMutableSet(): Converts the set to a mutable set.
intersect(Iterable<T> other): Returns the intersection of two sets.

Map Extension #

Type-safe extract and convert methods like getInt(key), getDateTime(key), getMap(key) etc.
makeEncodable: Converts a map to an encodable format.
safelyEncodedJson: Returns a safely encoded JSON string.
flatMap Flatten nested maps into single-level structures.
isEmptyOrNull: Checks if the map is empty or null.
isNotEmptyOrNull: Checks if the map is not empty or null.
setIfMissing Add entries conditionally.
update Update values based on a condition.
filter Filter entries using predicates.
keysList, valuesList, keysSet, valuesSet Get lists or sets of keys and values.

Number Extension #

For all `num` #

isSuccessHttpResCode: Checks if the HTTP response code is 200 or 201.
isValidPhoneNumber: Checks if the number is a valid phone number.
toHttpResStatus: Converts the number to an HttpResStatus enum.
tryToInt: Parses the number as an integer or returns null if it is not a number.
tryToDouble: Parses the number as a double or returns null if it is not a number.
percentage: Calculates the percentage of the number with respect to a total value, with an option to allow decimals.
asBool: Returns true if the number is greater than zero.
isPositive: Returns true if the number is positive.
isNegative: Returns true if the number is negative.
isZeroOrNull: Returns true if the number is zero or null.
isZero: Returns true if the number is zero.
isValidPhoneNumber: Checks if the number is a valid phone number.
numberOfDigits: Returns the number of digits in the number.
removeTrailingZero: Removes trailing zeros from the number's string representation.
roundToFiftyOrHundred: Rounds the number to the nearest fifty or hundred.
roundToTenth: Rounds the number to the nearest tenth.
tenth: Returns a tenth of the number.
fourth: Returns a fourth of the number.
third: Returns a third of the number.
half: Returns half of the number.
getRandom: Returns a random integer between 0 and the number.
asGreeks: Converts the number to a format that includes Greek symbols for thousands, millions, and beyond.
delay: Delays code execution by the number of seconds.
daysDelay: Delays code execution by the number of days.
hoursDelay: Delays code execution by the number of hours.
minDelay: Delays code execution by the number of minutes.
secDelay: Delays code execution by the number of seconds.
millisecondsDelay: Delays code execution by the number of milliseconds.
asMilliseconds: Converts the number to a Duration in milliseconds.
asSeconds: Converts the number to a Duration in seconds.
asMinutes: Converts the number to a Duration in minutes.
asHours: Converts the number to a Duration in hours.
asDays: Converts the number to a Duration in days.
until: Generates a sequence of numbers starting from the current number up to the specified end value, with the specified step size.

For `int` #

inRangeOf: Returns the number if it is within the specified range, otherwise returns the min or max value.
absolute: Returns the absolute value of the number.
doubled: Returns the number multiplied by two.
tripled: Returns the number multiplied by three.
quadrupled: Returns the number multiplied by four.
squared: Returns the square of the number.

For `double` #

inRangeOf: Returns the number if it is within the specified range, otherwise returns the min or max value.
absolute: Returns the absolute value of the number.
doubled: Returns the number multiplied by two.
tripled: Returns the number multiplied by three.
quadrupled: Returns the number multiplied by four.
squared: Returns the square of the number.

Duration Extension #

delayed(FutureOr<T> Function()? computation): Delays execution by the duration.
fromNow: Adds the Duration to the current DateTime and gives a future time.
ago: Subtracts the Duration from the current DateTime and gives a pastime.

Uri Extension #

isValidUri: Checks if the string is a valid URI.
toUri: Converts the string to a URI object.
isHttp: Checks if the URI uses the HTTP scheme.
isHttps: Checks if the URI uses the HTTPS scheme.
host: Returns the host part of the URI.
path: Returns the path part of the URI.

Bool Extension #

toggled: returns a new bool which is toggled from the current one.
val & isTrue: (nullable boolean): Returns true if the value is not null and true
isFalse: (nullable boolean): Returns true if the value is not null and false
binary: Returns 1 if the value is non-null and true, otherwise returns 0.

Objects Extension #

encode({Object? Function(dynamic object)? toEncodable}): Encodes an object to JSON.
isNull: Checks if the object is null.
isNotNull: Checks if the object is not null.
asBool: Converts an object to a boolean value.

Exceptions #

The ConvertObject class throws a ParsingException if there is an error while converting an object. This exception provides information about the type of the object and the method used for conversion.

Contributions #

Contributions to this package are welcome. If you have any suggestions, issues, or feature requests, please create a pull request in the repository.

License #

dart_helper_utils is available under the BSD 3-Clause License.

KEYWORDS: extension pack, helpers, utilities, string manipulation, conversions, time utils, date extension, datetime helper, DateFormat, intl, extensions, iterable, map, number, object, set, URI, and boolean extension, JSON encoding/decoding, parsing, safe parsing, object conversion, cast, list casting.

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Metadata

Table of Contents #

Featured #

Converting Objects #

Sample Usage: #

Available Conversions: #

Methods:

Static Methods: #

Optional Parameters: #

Example with listIndex:

Example with mapKey:

Auto Decoding of JSON Strings for Collections

Extract And Convert #

TimeUtils: #

Extensions #

Date Extensions #

Parsing #

Formatting #

Comparison #

Duration Calculation #

Manipulation #

Extensions For Intl #

DateFormat #

on String

on DateTime

NumberFormat #

on String

on Num

General #

on Map

on Num

on String

TextDirection #

Bidi #

on TextDirection

on String

String Extension #

Case Conversion #

Text Formatting #

String Replacement #

String Comparison #

String Limiting #

Character Checks #

Validation #

Utility #

Parsing #

Collection Extension #

Iterable Extension #

List Extension #

Set Extension #

Map Extension #

Number Extension #

For all num #

For int #

For double #

Duration Extension #

Uri Extension #

Bool Extension #

Objects Extension #

Exceptions #

Contributions #

License #

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dart_helper_utils 2.1.0
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Example with `listIndex`:

Example with `mapKey`:

For all `num` #

For `int` #

For `double` #