[Liberty-eiffel] Why aren'

[Laurie Moye]

Hi,

Could someone help me with a little problem please?

First, might I mention that in my previous post I said "infix 
operators... starting with #, which upset the compiler". That was just 
me getting confused, '#' is fine, but I would still appreciate knowing 
what characters are allowed in free operators.


My problem is with marix and vector classes which date back to Eiffel/S 
days. I think ES implemented polymorphism in a rudimentary way which 
made it really easy to define
"class VECTOR[ G -> NUMERIC ]".
When I converted the code to SmallEiffel, I could no longer make the 
polymorphism work, and had to expand it all out into classes like 
VECTOR_OF_REAL_64.

I am trying to make the polymorphic code work again in LE. Most of the 
code only uses the basic arithmetic operators which are declared in 
NUMERIC, but for some puropses I need to use features like 'abs'. These 
are not declared in NUMERIC, but when I found them in REAL_GENERAL and 
INTEGER_GENERAL, I thought I had found a way round this, but the 
compiler tells me:
" Fatal Error: The INTEGER_GENERAL type cannot be used here. Actually 
this is only a compiler implementation facility."

As all the real and integer classes have, for example, 'abs', why can't 
these common features be declared in NUMERIC so that I can use them in 
generic code for any numeric class?
Is there a way round this, or am I doomed to have to have classes like 
VECTOR_OF_REAL_64?

Best wishes,
        Laurie