Common C++ guidelines are to initialize variables on use and to make variables const whenever possible. But sometimes a variable is unchanged once initialized and the initialization is complex, like involving a loop. Then an IIFE – immediately-invoked function expression – can be used: the variable is initialized by a lambda that computes the value, which is then immediately invoked to produce the value. Then the variable is initialized on use and can also be made const. I’ve been recen...
