Stating failures first can also be considered analogous to input validation, preconditions, or declaring the domain for which the function is undefined. Some re

Stating failures first can also be considered analogous to input validation, preconditions, or declaring the domain for which the function is undefined. Some related discussion on here: http://c2.com/cgi/wiki?GuardClause http://c2.com/cgi/wiki?GuardClause