C++ FAQ Celebrating Twenty-One Years of the C++ FAQ!!!
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Section 18:
[18.9] What does "const X* x" mean?

const X* x and X const* x are equivalent. The real question is which should be used.

Answer: absolutely no one should pretend they can make decisions for your organization until they know something about your organization. One size does not fit all; there is no "right" answer for all organizations, so do not allow anyone to make a knee-jerk decision in either direction. "Think" is not a four-letter word.

For example, some organizations value consistency and have tons of code using const X*; for those, X const* would be a bad decision independent of its merits. There are lots of other business scenarios, some of which produce a preference for X const*, others a preference for const X*.

Use a style that is appropriate for your organization's average maintenance programmer. Not the gurus, not the morons, but the average maintenance programmer. Unless you're willing to fire them and hire new ones, make sure that they understand your code. Make a business decision based on your realities, not based on someone else's assumptions.

You'll need to overcome a little inertia to go with X const*. Most recent C++ books use X const*. However most older (ahem; "highly experienced") C++ programmers learned C++ with const X*. That doesn't mean const X* should be jettisoned as old-fashioned, nor does it mean X const* should be rejected as new-and-risky. You and your organization need to make an eyes-open decision whether and when to transition from const X* to X const*. During the transition there might be some confusion or mistakes, but some organizations are convinced the benefits of X const* outweigh the costs. Others, apparently, are not.

Another caveat: if you decide to use X const*, do something to make sure your people don't mis-type it as the semantically different but syntactically similar "X* const". Those two forms have completely different meanings even though they look similar at first blush.