Ledger
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a legder is a table of records that holds the history of an org, and of modpol itself.

its structure is a table of legder entries.

Every org has one, starting with the entry recording its creation.

Ledger Entry
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a legder entry is a table with the following properties:

timestamp = nil,
entrytype = nil,
action_msg = '',

the timestamp will hold the output of os.time at the moment the entry was created.

the entrytype is optional; it can hold an identifier of the kind of entry it is (e.g. 'org_init', 'new_user', etc etc.)

action_msg is the record output itself.



Entrytypes
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These are the entrytypes that modpol uses. Each additional module should document whatever entrytypes it adds.

'org_init'
type used when an org is created

'org_purge'
type used when all orgs are purged. -- will only be found in the main modpol ledger.

'org_remove'
type used when removing an individual org

'add_member'
type used when adding a member to an org

'remove_member'
type used when removing a member from an org



Old orgs
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when an org is removed, its ledger is stored in modpol.old_legders = {} Note that multiple ledgers may exist here with the same org name.