F# Inline Function

In F#, an inline function is a function that is expanded by the compiler at compile time. This means that the function call is replaced by the function body at the call site, making the code more efficient. Inline functions are particularly useful for operations that are performed frequently, such as looping and recursion.

Syntax

An inline function can be defined using the inline keyword followed by the function definition:

let inline functionName arguments = 
   functionBody

Example

Here is an example of an inline function that adds 1 to its argument:

let inline addOne x = x + 1

let y = addOne 4 // y has the value 5

Output

The output of the above example is as follows:

val inline addOne : x:'a -> 'a (+)

val y : int = 5

Explanation

In the above example, we have defined an inline function addOne that takes an argument x and adds 1 to it. The let keyword is used to bind the function to a value y by passing an argument 4 to addOne. The result of this expression is then stored in y, which has the value 5.

Use

Inline functions are useful when you need to optimize performance-critical code. By expanding the function call at the call site, the overhead of the function call is eliminated. This can lead to significant performance improvements in loops and other frequently executed operations.

Important Points

• Inline functions are expanded by the compiler at compile-time
• They are useful for optimizing performance-critical code
• They eliminate the overhead of function calls by expanding the function body at the call site

Summary

In this tutorial, we learned about F# inline functions. We saw the syntax and execution of an example, followed by an explanation of how and when to use inline functions. Finally, we highlighted some important points to keep in mind when using inline functions.