Re: [boost] [math] pow instantiates a number of templateproportional to the exponent

From: John Maddock (john_at_[hidden])
Date: 2008-05-15 04:20:17

Bruno Lalande wrote:
>> Hi,
>>
>>> Line 54:
>>>        return (N%2) ? base*positive_power<N-1>::result(base)
>>>
>>> in positive_power causes positive_power to be instantiated with all
>>> the integers from N down to 0.
>>
>> Yep you're right. At that moment I was a bit disturbed by this
>> runtime evaluation but I didn't think precisely about this issue so
>> I left it
>> like that.
>>
>> Adding a second integral template argument receiving N%2 to
>> specialize
>> on it works (see attachment) but I feel there's a more elegant
>> solution. Maybe using enable_if?

That's more or less what I did in the Sandbox version, but Hervé 
Brönnimann's solution looks more elegant maybe?

John.