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copied!<p>Grouping variable declarations at the top of the block is a legacy likely due to limitations of old, primitive C compilers. All modern languages recommend and sometimes even enforce the declaration of local variables at the latest point: where they're first initialized. Because this gets rid of the risk of using a random value by mistake. Separating declaration and initialization also prevents you from using "const" (or "final") when you could.</p> <p>C++ unfortunately keeps accepting the old, top declaration way for backward compatibility with C (one C compatibility drag out of many others...) But C++ tries to move away from it:</p> <ul> <li>The design of C++ references does not even allow such top of the block grouping.</li> <li>If you separate declaration and initialization of a C++ local <em>object</em> then you pay the cost of an extra constructor for nothing. If the no-arg constructor does not exist then again you are not even allowed to separate both!</li> </ul> <p>C99 starts to move C in this same direction.</p> <p>If you are worried of not finding where local variables are declared then it means you have a much bigger problem: the enclosing block is too long and should be split.</p> <p><a href="https://www.securecoding.cert.org/confluence/display/cplusplus/DCL19-CPP.+Initialize+automatic+local+variables+on+declaration" rel="noreferrer">https://www.securecoding.cert.org/confluence/display/cplusplus/DCL19-CPP.+Initialize+automatic+local+variables+on+declaration</a></p>

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