Re: [Axiom-developer] Nested functions in SPAD

[Gabriel Dos Reis]

Waldek Hebisch <address@hidden> writes:

| How to correctly define nested function in algebra file?  I changed
| beggining of goodCoef (in efstruc.spad.pamphlet) to the following:
| 
|     goodCoef(v, l, s) ==
|       -- if k1 is part of k2 we should not express k1 in terms of k2
|       -- (othewise we would get infinite recursion)
|       -- below we impose a stronger condition: we require
|       -- height(k1) to be maximal
|       h:NonNegativeInteger := 0
|       j:Integer := 0
|       transcendental?(k:K):Boolean ==
|          is?(k, "log"::SY) => true
|          is?(k, "exp"::SY) => true
|          is?(k, "tan"::SY) => true
|          is?(k, "atan"::SY) => true
|          false
|       ll := [k for k in l | transcendental?(k)]
| 
| that compiles OK, but at runtime I get:
| 
|    >> System error:
|    The function |EFSTRUC;transcendental?| is undefined.

Try:
    goodCoef(v, l, s) ==
      -- if k1 is part of k2 we should not express k1 in terms of k2
      -- (othewise we would get infinite recursion)
      -- below we impose a stronger condition: we require
      -- height(k1) to be maximal
      h:NonNegativeInteger := 0
      j:Integer := 0
      ll := [k for k in l | transcendental?(k)] where
         transcendental?(k:K):Boolean ==
            is?(k, "log"::SY) => true
            is?(k, "exp"::SY) => true
            is?(k, "tan"::SY) => true
            is?(k, "atan"::SY) => true
            false
      ll

-- Gaby