Yield Keyword

The yield keyword allows a function to produce a value without finishing all of its work. When execution reaches yield, the function pauses and preserves its current state, including local variables and its position in the function. A later request resumes execution from that saved point rather than starting again.

This behavior is the foundation of generators in languages such as Python and JavaScript. Instead of calculating an entire collection and storing it in memory, a generator can produce one value at a time as the caller asks for the next item. That makes yield useful for large sequences, stream processing, paginated results, and other workloads where values can be created lazily.

Yield changes control flow as well as memory behavior. The caller and generator alternate execution, which makes it possible to represent potentially long or even open-ended sequences without building them all in advance. Developers use it when incremental computation is clearer or more efficient than returning a fully materialized list.