# FullyRetractableTo SΒΆ

retract.spad line 1 [edit on github]

S: Type

A is fully retractable to `B`

means that A is retractable to `B`

, and, in addition, if `B`

is retractable to the integers or rational numbers then so is A. In particular, what we are asserting is that there are no integers (rationals) in A which don`'t`

retract into `B`

. Date Created: March 1990

- coerce: Fraction Integer -> % if S has RetractableTo Fraction Integer
from CoercibleFrom Fraction Integer

- coerce: Integer -> % if S has RetractableTo Integer
from CoercibleFrom Integer

- coerce: S -> %
from CoercibleFrom S

- retract: % -> Fraction Integer if S has RetractableTo Fraction Integer
from RetractableTo Fraction Integer

- retract: % -> Integer if S has RetractableTo Integer
from RetractableTo Integer

- retract: % -> S
from RetractableTo S

- retractIfCan: % -> Union(Fraction Integer, failed) if S has RetractableTo Fraction Integer
from RetractableTo Fraction Integer

- retractIfCan: % -> Union(Integer, failed) if S has RetractableTo Integer
from RetractableTo Integer

- retractIfCan: % -> Union(S, failed)
from RetractableTo S

CoercibleFrom Fraction Integer if S has RetractableTo Fraction Integer

CoercibleFrom Integer if S has RetractableTo Integer

RetractableTo Fraction Integer if S has RetractableTo Fraction Integer

RetractableTo Integer if S has RetractableTo Integer