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Section: 17.3.5.2 [numeric.limits.members] Status: NAD Submitter: Steve Cleary Opened: 2000-01-28 Last modified: 2016-01-28
Priority: Not Prioritized
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Discussion:
In several places in 17.3.5.2 [numeric.limits.members], a member is described as "Meaningful for all floating point types." However, no clear method of determining a floating point type is provided.
In 17.3.5.3 [numeric.special], paragraph 1 states ". . . (for example, epsilon() is only meaningful if is_integer is false). . ." which suggests that a type is a floating point type if is_specialized is true and is_integer is false; however, this is unclear.
When clarifying this, please keep in mind this need of users: what exactly is the definition of floating point? Would a fixed point or rational representation be considered one? I guess my statement here is that there could also be types that are neither integer or (strictly) floating point.
Rationale:
It is up to the implementor of a user define type to decide if it is a floating point type.