Four fours

Back in elementary school, I became aware of the four fours puzzle. It is a seemingly simple mathematical exercise where you must generate all the integers from 1 to 100 using arithmetic expressions and the digit 4 exactly four times.…

Loopy tests

Loops are fundamental structures in almost every programming language (we’ll put aside APL for the time being). In unit tests, however, loops can be a problem. This is especially true of loops in the “Assert” section. For instance, consider this…