loopfor

Loopfor is a term used in some programming language theory discussions and certain domain-specific languages to denote a looping construct that blends characteristics of a for loop with those of a while-style loop. It is not a widely standardized keyword in mainstream languages, but is used in educational materials and some languages to illustrate composite looping patterns.

In a typical loopfor syntax, there is an initialization phase that sets the loop variable, a condition that is checked before each iteration, and a step that updates the variable after each pass. The distinguishing feature is that the condition may include complex predicates beyond a simple upper or lower bound, and the step can incorporate multiple updates or side effects. The control flow is: initialize, check condition, execute body, perform step, repeat.

Loopfor is similar to a for loop in that it uses a central loop variable and a termination condition, but it also resembles a while loop in that the condition can be augmented with runtime predicates and can be influenced by external state inside the loop body. In practice, loopfor is mainly used as a teaching tool to illustrate how initialization, condition, and update interact, and in some DSLs it can yield more expressive iteration patterns than a traditional for.

Considerations include readability, predictability, and performance. Because loopfor can include complex conditions and non-trivial updates, its optimizations may be less straightforward than standard for-loops. Bugs can arise when the update step has side effects or when the condition depends on mutable state changed within the loop body.

See also: for loop, while loop, foreach, iterator, loop construct, programming language theory.