Transfers

When the application allows it, members give each other points: Transfers::transfer($from, $to, $amount, $key, $currency) checks the guards (Guards), moves the points by a transfer of the ledger under exchange:transfer: and the key — which never makes the giver's balance negative —, then writes the transfer to the journal.

$transfers->transfer($member, $friend, 50, 'gift:2026-11-07:44');

The same key gives once: asked again, the transfer already written is returned, the guards and the clock aside; the same key for another transfer is an ExchangeConflict.

The journal

The TransferLog keeps every transfer: journal($limit) gives the latest of every member, newest first, 50 unless asked otherwise and at most 1000 — what a moderator examines —; ofMember($member) gives those a member gave or received, oldest first; given($member, $currency) gives what a member gave over the allowance's current period, or ever without an allowance.