In C/C++, Visual Assist can add a forward declaration for a referenced symbol, e.g. a pointer to a class, to make an unknown symbol known. The forward declaration, if sufficient, typically reduces compile time relative to a comparable include directive.
Access
Hover over, or move the text caret to, an unknown symbol and access the Quick Action and Refactoring menu. Choose "Add Forward Declaration".
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The necessary forward declaration is inserted in a sensible location, e.g. after other forward declarations or after the first group of include directives.
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The position of the text caret is unchanged.
Add Forward Declaration versus Add include Directive
Visual Assist offers to add a forward declaration based only on a reference to a symbol. Visual Assist does not assess references to other symbols to determine if an include directive is more appropriate, or necessary. Hence, for every symbol that can be resolved by a forward declaration, Visual Assist also offers to resolve the symbol via an include directive.
Select the method more appropriate, or necessary, for the entire header.