Clarify the direction predicates for cursor iteration (#457)

* Clarify the direction predicates for cursor iteration

Co-authored-by: Joshua Bell <[email protected]>

Author: stelar7

index.bs

@@ -5911,63 +5911,53 @@ To <dfn>iterate a cursor</dfn> with |targetRealm|, |cursor|, an optional
               Let |found record| be the first record in |records| which
               satisfy all of the following requirements:
 
-              * If |key| is defined, the record's key is [=greater
-                  than=] or [=equal to=] |key|.
+              * If |key| is defined:
+                  * The record's key is [=greater than=] or [=equal to=] |key|.
 
-              * If |primaryKey| is defined, the record's key is [=equal
-                  to=] |key| and the record's value is [=greater
-                  than=] or [=equal to=] |primaryKey|, or the
-                  record's key is [=greater than=] |key|.
+              * If |primaryKey| is defined:
+                  * The record's key is [=equal to=] |key| and the record's value is [=greater than=] or [=equal to=] |primaryKey|
+                  * The record's key is [=greater than=] |key|.
 
-              * If |position| is defined, and |source| is an
-                  [=/object store=], the record's key is [=greater than=]
-                  |position|.
+              * If |position| is defined and |source| is an [=/object store=]:
+                  * The record's key is [=greater than=] |position|.
 
-              * If |position| is defined, and |source| is an
-                  [=/index=], the record's key is [=equal to=]
-                  |position| and the record's value is [=greater
-                  than=] |object store position| or the record's key is
-                  [=greater than=] |position|.
+              * If |position| is defined and |source| is an [=/index=]:
+                  * The record's key is [=equal to=] |position| and the record's value is [=greater than=] |object store position|
+                  * The record's key is [=greater than=] |position|.
 
-              * The record's key is [=in=]
-                  |range|.
+              * The record's key is [=in=] |range|.
 
           : "{{IDBCursorDirection/nextunique}}"
           ::
               Let |found record| be the first record in |records| which
               satisfy all of the following requirements:
 
-              * If |key| is defined, the record's key is [=greater
-                  than=] or [=equal to=] |key|.
+              * If |key| is defined:
+                  * The record's key is [=greater than=] or [=equal to=] |key|.
 
-              * If |position| is defined, the record's key is [=greater
-                  than=] |position|.
+              * If |position| is defined:
+                  * The record's key is [=greater than=] |position|.
 
-              * The record's key is [=in=]
-                  |range|.
+              * The record's key is [=in=] |range|.
 
           : "{{IDBCursorDirection/prev}}"
           ::
               Let |found record| be the last record in |records| which
               satisfy all of the following requirements:
 
-              * If |key| is defined, the record's key is [=less
-                  than=] or [=equal to=] |key|.
+              * If |key| is defined:
+                  * The record's key is [=less than=] or [=equal to=] |key|.
 
-              * If |primaryKey| is defined, the record's key is [=equal
-                  to=] |key| and the record's value is [=less than=]
-                  or [=equal to=] |primaryKey|, or the record's key is
-                  [=less than=] |key|.
+              * If |primaryKey| is defined:
+                  * The record's key is [=equal to=] |key| and the record's value is [=less than=] or [=equal to=] |primaryKey|
+                  * The record's key is [=less than=] |key|.
 
-              * If |position| is defined, and |source| is an
-                  [=/object store=], the record's key is [=less
-                  than=] |position|.
+              * If |position| is defined and |source| is an [=/object store=]:
+                  * The record's key is [=less than=] |position|.
 
-              * If |position| is defined, and |source| is an
-                  [=/index=], the record's key is [=equal to=]
-                  |position| and the record's value is [=less than=]
-                  |object store position| or the record's key is
-                  [=less than=] |position|.
+              * If |position| is defined and |source| is an [=/index=]:
+                  * The record's key is [=equal to=] |position| and the record's value is [=less than=] |object store position|
+                  * The record's key is [=less than=] |position|.
 
               * The record's key is [=in=] |range|.
 
@@ -5976,14 +5966,13 @@ To <dfn>iterate a cursor</dfn> with |targetRealm|, |cursor|, an optional
               Let |temp record| be the last record in
               |records| which satisfy all of the following requirements:
 
-              * If |key| is defined, the record's key is [=less
-                  than=] or [=equal to=] |key|.
+              * If |key| is defined:
+                  * The record's key is [=less than=] or [=equal to=] |key|.
 
-              * If |position| is defined, the record's key is [=less
-                  than=] |position|.
+              * If |position| is defined:
+                  * The record's key is [=less than=] |position|.
 
-              * The record's key is [=in=]
-                  |range|.
+              * The record's key is [=in=] |range|.
 
               If |temp record| is defined, let |found record| be the
               first record in |records| whose [=/key=] is [=equal to=]
@@ -6728,6 +6717,7 @@ For the revision history of the second edition, see [that document's Revision Hi
 * Add [=cursor/source handle=] to [=/cursor=] to avoid exposing internal indexes and object stores to script. (<#445>)
 * Define [=Queue a database task=] and replace [=Queue a task=] with it (<#421>)
 * Add missing parallel step to {{IDBFactory/databases()|databases}}() (<#421>)
+* Clarify cursor iteration predicates (<#450>)
 
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 # Acknowledgements # {#acknowledgements}