Re: [clisp-list] pi seems not to be a constant

[Pascal J. B. <pj...@in...>]

On 16/10/15 09:21, Don Cohen wrote:
> [1]> (lisp-implementation-version) ; built from current source
> "2.49+ (2010-07-17) (built 3653902709) (memory 3653902846)"
> [2]> (constantp 'pi) ; I think this should return T
> NIL
> [3]> (defconstant pi2 pi)
> PI2
> [4]> (constantp 'pi2)
> T
> [5]>
>

The problem is that in clisp, CL:PI is not constant


[1]> pi
3.1415926535897932385L0
[2]> (setf (ext:long-float-digits) 1000)
1000
[3]> pi
3.141592653589793238462643383279502884197169399375105820974944592307816406286208998628034825342117067982148086513282306647093844609550582231725359408128481117450284102701938521105559644622948954930381964428810975665933446128475648233786783165271201909145648566923460348610454326648213393607260249141273724587L0 

[4]>

Conformity could be restored by having CL:PI defined as a constant 
variable bound to double-float π, and to have another variable EXT:PI 
bound to the changing long-float π value.

-- 
__Pascal J. Bourguignon__
http://www.informatimago.com/