Pattern matching, let...else
let...else
tries to make a variable and by the time it moves out the let...else
block it is expected that that variable has been created and has a value in it. This property is made possible by diverging code
let...else
tries to make a variable and by the time it moves out the let...else
block it is expected that that variable has been created and has a value in it. This property is made possible by diverging code