rework "forgettable" marking documentation

- add anchor prior for "Private order data cleanup"
- remove FIXME blurb
- drop ‘ContractTerms._forgettable’
- add para describing "peer ‘_forgettable’" fields
- add internal link to ‘private-order-data-cleanup’

1 files changed, 8 insertions, 7 deletions

diff --git a/core/api-merchant.rst b/core/api-merchant.rst
index b2b2b2ff..38a99ad6 100644
--- a/core/api-merchant.rst
+++ b/core/api-merchant.rst
@@ -1912,6 +1912,8 @@ Inspecting orders
 
 
 
+.. _private-order-data-cleanup:
+
 Private order data cleanup
 --------------------------
 
@@ -2763,9 +2765,6 @@ This section describes the overall structure of
 the contract terms that are the foundation for
 Taler payments.
 
-FIXME: the "forgettable" attribute is not
-properly specified here!
-
 .. _contract-terms:
 
 The contract terms must have the following structure:
@@ -2891,10 +2890,6 @@ The contract terms must have the following structure:
     // Useful when the merchant needs to store extra information on a
     // contract without storing it separately in their database.
     extra?: any;
-
-    // List of forgettable fields.  Each element in the list is
-    // a jq(1)-style path.
-    _forgettable: String[];
   }
 
 The wallet must select a exchange that either the merchant accepts directly by
@@ -3019,3 +3014,9 @@ It has the following structure:
     // Master public key of the exchange.
     master_pub: EddsaPublicKey;
   }
+
+In addition to the fields described above,
+each object (from ``ContractTerms`` down)
+can mark certain fields as "forgettable" by listing the names of those fields
+in a special peer field ``_forgettable``.
+(See :ref:`Private order data cleanup <private-order-data-cleanup>`.)