Joshua Juran wrote:
scalar
number (possibly complex)
real
rational
integer
Integer
BigInt
Ratio
Float
Complex
Quaternion
String
...
Trying to fit every problem into a rigid inheritance tree is perhaps the
failure of the strict Class-based Object Oriented paradigm; that is, if
you count multiple inheritance and interfaces as afterthoughts rather
than the intent of Class-based Inheritance.
With reference to this Venn diagram:
http://svn.openfoundry.org/pugs/ext/Perl-MetaModel/docs/number-types.png
Here are the corresponding Rule descriptions; structure stolen from Haskell;
role Num;
role Real does Num;
role Fractional does Num;
role Integral does Real;
class Int does Integral;
class int does Integral; # unboxed...
role RealFrac does Real does Fractional;
class Rational does RealFrac;
class IntRatio does RealFrac;
role Floating does Fractional;
role RealFrac does Floating;
role RealFloat does RealFrac does Floating;
class Float does RealFloat;
class Double does RealFloat;
class ComplexFloat does Floating;
class ComplexDouble does Floating;
I would suggest this as a good starting point. One thing that Haskell
is good at is math.
Sam.
