|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| • | The persistence
of a value is |
|||||||||||||||||
| – | the length of
time for which it is valuable to the on-going |
|||||||||||||||||
| computation |
||||||||||||||||||
| • | E.g.
sub-expression, block, fn invocation, package, program |
|||||||||||||||||
| invocation,
program lifetime, system lifetime |
||||||||||||||||||
| • | Orthogonal
persistence |
|||||||||||||||||
| – | the persistence
of data values is independent, or orthogonal, |
|||||||||||||||||
| to all other
properties of the value (such as type, constancy, |
||||||||||||||||||
| naming) |
||||||||||||||||||
| – | Cf. trad.
systems where ONLY files have long-term |
|||||||||||||||||
| persistence |
||||||||||||||||||
