Versions: Swift (5.4.2), Dart (2.13.4), Kotlin
| Dart | Kotlin | Swift |
|---|---|---|
// Implicit type = int
var myVariable = 5;
// Explicit type: String
String name = "Kral";
// Dynamic type: dynamic
dynamic dinamik = "Dynamic";
dinamik = 5; // Valid
// Constant
final name = "Enes";
const name = "Enes";
// Anything that isn't known at
// compile time
// should be final over const. |
// Implicit type = Int
var myVariable = 5
// Explicit type: String
var name: String = "Kral"
// Dynamic type: dynamic
var dinamik: dynamic = "String"
dinamik = 5 // Valid
// Constant
const val name = "Enes"
val name = "Enes" |
// Implicit type = Int
var myVariable = 5
myVariable = "a string" // Invalid
// Explicit type: String
var name: String = "Kral"
// Dynamic type: Any
var dinamik: Any = "String"
dinamik = 5 // Valid
// Constant
let gender = "Man"
gender = "Woman" // Invalid |
// Enum
enum Color { red, green, blue }
var aColor = Color.blue;
// aColor has index, hashCode & toString() parameters by default.
// Enum cases can not contain associated values like in Swift.
// Computed variables & Functions can't be added directly to the enum.
// But they can be added via an extension.
extension DarkMode on Color {
Color get darkModeAlternative {
switch (this) {
case Color.blue: return Color.red;
default: return Color.blue;
}
}
} |
// Enum
enum class Color {RED, GREEN, BLUE}
var aColor = Color.BLUE |
// Enum
enum MessageKind {
case placeholder
// Associated values allowed.
case image(URL)
case text(String)
// Computed variables & Static variables allowed.
var debugPrint: String {
switch self {
case .image(let url):
return "Url: \(url)"
case .text(let text):
return "Text: \(text)"
default:
return "Placeholder"
}
}
// Functions are allowed as well.
func debugPrintFoo() -> String {
debugPrint
}
} |
typedef GestureTapCallback = void Function(); |
// Fill |
// Type alias
typealias TapCallback = () -> Void |
// Check type
if (myVariable is String) { .. } |
// Fill |
// Check type
if myVariable is String { .. } |
| Dart | Kotlin | Swift |
|---|---|---|
// Declaration
var string1 = "String";
var string2 = 'String';
// Multiline
var multilineStr = """
Here you can have your string multiline for easier readability;
Start & end with 3 quote character.
""";
// String interpolation
var name = "Enes";
print("Hello $name");
print("For objects use ${person.name}"); |
// Declaration
var string1 = "String"
// Multiline
var multilineStr = """
Here you can have your string multiline for easier readability;
Start & end with 3 quote character.
"""
// String interpolation
var name = "Enes";
print("Hello $name");
print("For objects use ${person.name}"); |
// Declaration
let string = "String"
// Multiline
let multilineStr = """
Here you can have your string multiline for easier readability;
Start & end with 3 quote character.
"""
// String interpolation
let name = "Enes"
print("Hello \(name)")
print("For objects use \(person.name)") |
| Dart | Kotlin | Swift |
|---|---|---|
// Declaration
String greet(String name) {
return "Hey $name";
}
// Optional named parameters
void greet(String name) { }
greet("Enes");
// Named parameters
void greet({required String name}) { }
greet(name: "Enes")
// Default parameters
void greet({String name = "Enes"}) { }
greet();
greet(name: "Kral");
// Var args
// N/A
// List can be used to achieve
// similar behaviour
// or visit `VarArgs` package below.
// Closure/Lambda
var square = (int x) => x * x;
square(4); |
// Declaration
fun greet(name: String): String {
return "Hey $name"
}
// Optional named parameters
fun greet(name: String = "No Name") { }
greet("Enes");
// Named parameters
fun greet(name: String) { }
greet("Enes")
// Default parameters
fun greet(name: String = "Enes") { }
greet();
greet(name: "Kral"); |
// Declaration
func greet(name: String) -> String {
// return keyword is optional if body contains single (code) line
return "Hey \(name)"
}
// Optional named parameters
func greet(_ name: String) { }
greet("Enes")
// Named parameters
func greet(name: String) { }
greet(name: "Enes")
// Default parameters
func greet(name: String = "Enes") { }
greet()
greet(name: "Adam")
// Var args
func greet(_ names: String...) { }
greet("Enes", "Egemen", "Ferid", "Serkan")
// Closure/Lambda
var square: (Int) -> Int = { $0 * $0 }
var square = { (x: Int) -> Int in
return x * x
}
square(4) |
| Dart | Kotlin | Swift |
|---|---|---|
// if & else(if)
if (isRaining()) {
you.bringRainCoat();
} else if (isSnowing()) {
you.wearJacket();
} else {
car.putTopDown();
}
// for loops
for (var i = 0; i < 5; i++) {
print('Flutter ${i + 1}');
}
// for-in
var obj = ["Android","iOS","Flutter"];
for (var prop in obj) {
print(prop);
}
// for-each
var collection = ["Android", "iOS", "Flutter"];
collection.forEach(print);
// or
var callbacks = [];
for (var i = 0; i < 2; i++) {
callbacks.add(() => print(i));
}
callbacks.forEach((c) => c());
// while
while (!isDone()) {
doSomething();
}
// do-while
do {
printLine();
} while (!atEndOfPage());
// break
while (true) {
if (shutDownRequested()) break;
processIncomingRequests();
}
// continue
for (int i = 0; i < candidates.length; i++) {
var candidate = candidates[i];
if (candidate.yearsExperience < 5) {
continue;
}
candidate.interview();
}
// or
candidates
.where((c) => c.yearsExperience >= 5)
.forEach((c) => c.interview());
// switch-case
var option = 1;
switch (option) {
case 1:
print("Android");
break;
case 2:
print("iOS");
break;
default:
print("Flutter");
break;
}
// switch-continue
var option = 1;
switch (option) {
case 1:
print("Android");
continue testCase;
testCase:
case 2:
print("iOS");
break;
}
|
// Fill |
// if & else(if)
if isRaining() {
you.bringRainCoat()
} else if isSnowing() {
you.wearJacket()
} else {
car.putTopDown()
}
// for loops
// swift does not have C like for loops
for i in 0..<5 {
print("Swift \(i + 1)")
}
// for-in
var collection = ["Android", "iOS", "Flutter"]
for item in collection {
print(item)
}
// for-each
collection.forEach {
print($0)
}
// while
while !isDone() {
doSomething()
}
// repeat-while
repeat {
printLine()
} while !atEndOfPage()
// break
while true {
if (shutDownRequested()) break
processIncomingRequests()
}
// continue
for candidate in candidates {
if candidate.yearsExperience < 5 { continue }
candidate.interview()
}
// or
candidates
.filter { $0.yearsExperience >= 5 }
.forEach { $0.interview() }
// switch-case
var option = 1
switch option {
case 1:
print("Android")
case 2:
// ranges also supported -> case 2...5:
// ranges also supported -> case 2..<6:
print("iOS")
default:
print("Flutter")
}
// Prints "Android"
// switch-continue
var option = 1
switch option {
case 1:
print("Android");
fallthrough
case 2:
print("iOS")
default:
print("Flutter");
}
// Prints "Android" & "iOS" |
| Dart | Kotlin | Swift |
|---|---|---|
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| Dart | Kotlin | Swift |
|---|---|---|
// Declaration
String str = null; // Invalid
String? str = null; // Valid
str?.toUpperCase(); // Safe call
String? str = "enes";
str?.toUpperCase(); // "ENES"
// Null aware operator
int? id = null;
var userId = id ?? -1; // -1
int? id = 53;
var userId = id ?? -1; // 53 |
// Fill |
// Declaration
var str: String = nil // Invalid
var str: String? = nil // Valid
str?.uppercased() // Safe call
var str: String? = "enes";
str?.uppercased() // Optional("ENES")
// Nil Coalescing operator
var id: Int? = nil
var userId = id ?? -1 // -1
var id: Int? = 53;
var userId = id ?? -1; // 53 |
| Dart | Kotlin | Swift |
|---|---|---|
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| Dart | Kotlin | Swift |
|---|---|---|
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