NewValidationError returns a new ValidationError.

Email is a validator that checks if the value is a valid email address.

ValidateStruct validate struct data - s: struct pointer - return: validation errors as url.Values or nil if no errors.

ErrValidation is returned when validation fails.

EmailAddress is a structure that stores the address local-part@domain parts.

ValidationError is a custom error type that contains a map of field names to error messages.