developer-roadmap/roadmaps/cpp/content/forward-declaration@ZHjU60uzJTezADRhDTESG.md

Forward Declaration

Forward declaration is declaring an identifier (like a class, function, or variable) to the compiler before its full definition is provided. This informs the compiler about the existence and type of the identifier, allowing it to be used in limited contexts, such as pointer or reference usage, without requiring the full definition to be immediately available. This technique helps to manage dependencies, reduce compilation times, and resolve circular dependencies between different parts of a codebase.