Lambda expressionsare actually anonymous functions in Kotlin. Therefore, we can pass a lambda expression as a function tojoinByOperation()like this: joinByOperation(aStringList, { lambda expression })Copy Additionally,when a function’s final parameter is a function, Kotlin allows us to place the ...
文章目录 一、run 标准库函数 1、run 函数传入 Lambda 表达式作为参数 2、run 函数传入函数引用作为参数 Kotlin 语言中 , 在 Standard.kt 源码中 , 为所有类型定义了一批标准库函数..., 所有的 Kotlin 类型都可以调用这些函数 ; 一、run 标准库函数 --- 1、run 函数传入 Lambda 表达式作为参数 run 标准库函...
println("result =$result")// The last expression in a lambda is considered the return value:result })// Parameter types in a lambda are optional if they can be inferred:valjoinedToString = items.fold("Elements:", { acc, i -> acc +" "+ i })// Function references can also be used...
Kotlin now supports SAM conversion for Kotlin interfaces. Note that it works differently than in Java: You need to mark functional interfaces explicitly. After you mark an interface withfunkeyword, you instead can pass a lambda as an argument whenever such an interface is expected as a parameter...
Notice that you can also declare the parameter yourself explicitly. This is a better choice if you have nested lambda. The second convention applies only if a lambda is passed as argumentof the last parameterof a function. In such cases you can write the lambda outside the parentheses. If ...
Also, thelateinitmodifier can now be used ontop-level propertiesandlocal variables. The latter can be used, for example, when you’re initializing an object graph and you have a circular dependency between the properties of the objects in the graph (e.g. the lambda passed as a constructor ...
If a vararg parameter is not the last one in the list, values for the following parameters can be passed using the named argument syntax, or, if the parameter has a function type, by passing a lambda outside parentheses. When we call a vararg-function, we can pass arguments one-by-one...
A Scoped mock is a mock that automatically unmocks itself after the code block passed as a parameter has been executed. You can use the mockkObject, mockkStatic and mockkConstructor functions.object ObjBeingMocked { fun add(a: Int, b: Int) = a + b } // ObjBeingMocked will be un...
So passing nullable type as a type argument or type parameter produces a warning. Annotating type arguments and type parameters works with the Java 8 target or higher. The feature requires that the nullability annotations support theTYPE_USEtarget (org.jetbrains.annotationssupports this in version 15...
Since the last parameter is a lambda, we can omit the parenthesis and move the lambda block out of it:val thread = Thread { // the logic }Simply put, even though the Java API is expecting a functional interface from us, we’re still able to pass the corresponding lambda to it. ...