E3027

guard! cannot have an else clause. It is the explicit form of a terminating guard: when its condition is false or its pattern does not match, the program terminates.

Erroneous example

///|
pub fn require(condition : Bool) -> Bool {
  guard! condition else { false }
  true
}

Suggestion

Use guard when an else clause is needed.

///|
pub fn require(condition : Bool) -> Bool {
  guard condition else { false }
  true
}