ISO/IEC TS 22277:2017 describes extensions to the C++ Programming Language (Clause 2) that enable definition of coroutines. These extensions include new syntactic forms and modifications to existing language semantics.

The International Standard, ISO/IEC 14882:2014, provides important context and specification for this document. This document is written as a set of changes against that specification. Instructions to modify or add paragraphs are written as explicit instructions. Modifications made directly to existing text from the International Standard use underlining to represent added text and strikethrough to represent deleted text.