Stops the evaluation of the enclosing while expression or for expression. In other words, a break expression is semantically equivalent to transferring control to just after the final statement of the loop body, and then performing no further iterations. If a break-expression-result is present, the expression (the result) becomes the result of the enclosing while expression or for expression.
Any defer statements that would go out of scope due to the control transfer are executed before stopping the loop.
It is a semantic error for a break expression to appear outside of the loop body of a while expression or for expression. If a break expression appears in the body of a defer statement, it cannot bind to a while expression or for expression outside of the body.
A break expression has no result value.