deferhelper

README

deferhelper

Helpers for Go's defer statement.

Documentation

Overview

Package deferhelper contains defer-related helpers.

Index

• func BeforeAfter(before, after func()) func()
• func WriteBeforeAfter(w io.Writer, before, after []byte) func()
• func WriteStringBeforeAfter(w io.Writer, before, after string) func()

Examples

• BeforeAfter
• WriteStringBeforeAfter

Functions

func BeforeAfter

func BeforeAfter(before, after func()) func()

BeforeAfter, if called in the following manner from a defer statement at the very beginning of a function,

	func Example() {
	  defer deferhelper.BeforeAfter(before(), after())()
    // do something
	}

will call 'before' function before executing the function code and 'after' function after executing the function code.

Example

defer BeforeAfter(func() { fmt.Println("before") }, func() { fmt.Println("after") })()
fmt.Println("in the middle")

Output:

before
in the middle
after

func WriteBeforeAfter

func WriteBeforeAfter(w io.Writer, before, after []byte) func()

WriteBeforeAfter is like BeforeAfter but writes 'before' and 'after' slices to 'w' before and after executing the function code.

func WriteStringBeforeAfter

func WriteStringBeforeAfter(w io.Writer, before, after string) func()

WriteStringBeforeAfter is like BeforeAfter but writes 'before' and 'after' strings to 'w' before and after executing the function code.

Example

defer WriteStringBeforeAfter(os.Stdout, "before\n", "after\n")()
fmt.Println("in the middle")

Output:

before
in the middle
after