This is the base class of closed form expression, inherited from bandicoot::BASE.
See also
Parent class: bandicoot::BASE
New attributes: CLOSED_FORM$sym, CLOSED_FORM$sym_name,
CLOSED_FORM$sym_type, CLOSED_FORM$expr
New methods: CLOSED_FORM$..init.., CLOSED_FORM$..str..,
CLOSED_FORM$..len..,
CLOSED_FORM$compute, CLOSED_FORM$gen, CLOSED_FORM$ast,
CLOSED_FORM$as_dataframe