## Return True Only When One of the Three Inputs Is True

At the $DAYJOB I was trying to figure out how to have a contract for a function that ensures that only one of the three conditionals needed is true. Given that I had come from an electrical engineering background, my first thought was to write a boolean expression. One goes about this by first constructing a truth table and either forming an expressing with a “Sum of Products” (SOP) or a “Product of Sums” expression from the table.