ChernClassVariableTable -- the class of all Chern class variable tables

Description

After creating a Chern class variable such as chern_3 E, the base symbol E acquires as value a hash table that holds the values of the Chern class variables based on it. If something else is assigned to E, the values are no longer referred to by E, and will the space they occupy be collected and reused unless other references to them remain.

i1 : chern_3 E

o1 = c E
      3

o1 : ChernClassVariable

i2 : E

o2 = E

o2 : ChernClassVariableTable

i3 : peek E

o3 = ChernClassVariableTable{symbol$ => E}

i4 : chern_3 symbol E <- 44

o4 = 44

i5 : chern_3 E

o5 = 44

i6 : peek E

o6 = ChernClassVariableTable{3 => 44     }
                             symbol$ => E

i7 : E = 55

o7 = 55

i8 : chern_3 symbol E <- 44
--warning: clearing value of symbol E to allow access to Chern class variables based on it

o8 = 44

Methods that use an object of class ChernClassVariableTable:

chern(ZZ,ChernClassVariableTable) -- get value of a Chern class variable

For the programmer

The object ChernClassVariableTable is a type, with ancestor classes MutableHashTable < HashTable < Thing.