Recover
Last updated
Last updated
This Go code demonstrates the use of the recover
function to catch and handle panics within a deferred function. Let's go through the code with inline comments and explanations:
Explanation:
mayPanic()
:
This function deliberately panics with the custom error message "a problem."
defer func() { ... }()
:
The defer
statement is used to schedule the execution of an anonymous function to be performed when the surrounding function (main
in this case) exits.
The anonymous function includes a recover()
call, which returns nil
if there is no panic or the value passed to panic
if a panic occurred.
if r := recover(); r != nil { ... }
:
Inside the deferred function, the recover
function is used to catch a panic.
If a panic occurred, the recovered value (error message in this case) is printed.
mayPanic()
:
This line calls the mayPanic
function, which intentionally panics.
fmt.Println("After mayPanic()")
:
If there was no panic or if the panic was recovered successfully, this line will be executed.
If a panic occurred and was caught by the deferred function, the program will continue executing from this point.
Using recover
in a deferred function is a common pattern for handling panics and performing cleanup or logging operations before the program exits. It allows you to gracefully recover from unexpected errors and continue with the execution of the program.