Exercise-Errors

README

Copy your Sqrt function from the earlier exercise and modify it to return an error value.

Sqrt should return a non-nil error value when given a negative number, as it doesn't support complex numbers.

Create a new type

type ErrNegativeSqrt float64 and make it an error by giving it a

func (e ErrNegativeSqrt) Error() string method such that ErrNegativeSqrt(-2).Error() returns "cannot Sqrt negative number: -2".