/usr/share/axiom-20170501/src/algebra/CELL.spad is in axiom-source 20170501-3.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75  | )abbrev domain CELL Cell
Cell(TheField) : SIG == CODE where
  TheField : RealClosedField
  ThePols ==> Polynomial(TheField)
  O       ==> OutputForm
  B       ==> Boolean
  Z       ==> Integer
  N       ==> NonNegativeInteger
  BUP     ==> SparseUnivariatePolynomial(TheField)
  SCELL   ==> SimpleCell(TheField,BUP)
  SIG ==> CoercibleTo(O) with
     samplePoint : % -> List(TheField)
     dimension : % -> N
     hasDimension? :  (%,Symbol) -> B
     makeCell : List(SCELL) -> %
     makeCell : (SCELL,%) -> %
     mainVariableOf : % -> Symbol
     variablesOf : % -> List Symbol
     projection : % -> Union(%,"failed")
  CODE ==> add
    Rep := List(SCELL)
    coerce(c:%):O == 
      paren [sc::O for sc in c]
    projection(cell) ==
      null cell => error "projection: should not appear"
      r := rest(cell)
      null r => "failed"
      r
    makeCell(l:List(SCELL)) == l
    makeCell(scell,toAdd) == cons(scell,toAdd)
    mainVariableOf(cell) == 
      null(cell) => 
        error "Should not appear"
      variableOf(first(cell))
    variablesOf(cell) ==
      null(cell) => []
      cons(mainVariableOf(cell),variablesOf(rest(cell)::%))
    dimension(cell) ==
      null(cell) => 0
      hasDimension?(first(cell)) => 1+dimension(rest(cell))
      dimension(rest(cell))
    hasDimension?(cell,var) ==
      null(cell) => 
        error "Should not appear"
      sc : SCELL := first(cell)
      v := variableOf(sc)
      v = var => hasDimension?(sc)
      v < var => false
      v > var => true
      error "Caca Prout"
    samplePoint(cell) ==
      null(cell) => []
      cons(samplePoint(first(cell)),samplePoint(rest(cell)))
 |