class UpdateSeq

This is a sequence number that increments monotonically. It can be used to track cache updates, or serve as a kind of timestamp for any changing properties.

A special class is used instead of simply an int, so we can elegantly handle such things as wraparound and special cases. There are two special cases. Firstly, a sequence number is ‘initial’ when it is first created. This sequence is older than any other sequence number. Secondly, a sequence number may be explicitly set to ‘old’. This is older than any other sequence number except ‘initial’. Finally, we have the explicit number ‘fresh’, which is newer than any other sequence number. All other sequences are numeric and are monotonically increasing.

Inheritance diagram

__init__() → None

Creates an UpdateSeq in the ‘initial’ state.

__init__(copy: UpdateSeq) → None
assign(copy: UpdateSeq) → UpdateSeq
Return type

clear() → None

Resets the UpdateSeq to the ‘initial’ state.

static fresh() → UpdateSeq
Return type

getSeq() → Integer

Returns the internal integer value associated with the UpdateSeq. Useful for debugging only.

Return type

Integer

increment(param0: int) → UpdateSeq
Return type

increment(param0: int) → UpdateSeq
Return type

static initial() → UpdateSeq
Return type

isFresh() → bool

Returns true if the UpdateSeq is in the ‘fresh’ state.

isInitial() → bool

Returns true if the UpdateSeq is in the ‘initial’ state.

isOld() → bool

Returns true if the UpdateSeq is in the ‘old’ state.

isSpecial() → bool

Returns true if the UpdateSeq is in any special states, i.e. ‘initial’, ‘old’, or ‘fresh’.

static old() → UpdateSeq
Return type

output(out: ostream) → None
property seq