Nextwhile

Nextwhile is a term used to describe a looping construct found in some programming languages and domain-specific languages. It combines the idea of a while loop with an emphasis on advancing to the next iteration, and in languages that implement it as a distinct keyword, it is sometimes used to express loop continuity more succinctly. There is no universal standard definition, and the exact syntax and behavior can vary between languages.

In languages that implement nextwhile as a dedicated keyword, the typical form is a condition followed by a block of code, for example: nextwhile (condition) { body }. The loop tests the condition at the start of each iteration; if the condition is true, the body executes and the loop proceeds to the next iteration; if false, the loop terminates. Some languages achieve similar behavior using a while loop with an explicit next or continue at the end of the body, effectively yielding the same control flow: the body runs, then the next iteration begins by rechecking the condition.

Nextwhile is generally viewed as a variant of the classic while loop, with a naming emphasis on continuing to the next iteration. It is more common in experimental, educational, or language-design contexts than in mainstream production languages. Where it exists, it is typically interchangeable with a standard while loop, provided the language semantics are aligned.

Related constructs include the standard while loop, do-while or repeat-until forms, and the continue or next statements in various languages. See also: while loop, do-while loop, continue statement.