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When multiple statements are used in a macro, they should be bound together in a do-while loop syntactically, so the macro can appear safely inside if clauses or other places that expect a single statement or a statement block. Note that this is only effective if none of the multiple statements are break or continue, as they would be captured by the do-while loop. (Alternatively, when an if, for, or while statement uses braces even for a single body statement, then multiple statements in a macro will expand correctly even without a do-while loop (see EXP19-C. Use braces for the body of an if, for, or while statement).
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