Where are the limits for Qt types?

c++ qt limits numeric-limits
Cory Klein picture Cory Klein · Jan 25, 2011 · Viewed 27.2k times · Source

Regularly, I could reference limits.h to see what the max is for a certain type, like an int or long.

In Qt, there are types like qlonglong. Is there a header file and/or documentation that can be used in a similar way to manually or programmatically reference the limits of these types?

Answer

fbrereto picture fbrereto · Jan 25, 2011

There's a high likelihood the Qt types distill down to one of the basic types for which numeric_limits are defined. Have you tried calling e.g., std::numeric_limits<qlonglong>::max()?

As MSalters points out, too, if the types are not builtin numeric_limits can still be specialized for them. If that were the case one would hope Qt would include them.

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