Release v6.9.0

Projections can now express read models that used to need a reducer: dictionary entries keyed from the event, set-once values and ordered children.

Added

• set once <property> = <value> assigns a projection property only while it has no value, for values such as who created an entry and when (#1220)
• Dictionary entries keyed from the event's content with <property>.$eventContent.<path>, and from $causedBy.subject, .name or .userName, alongside the existing $eventContext keys
• remove <property>.$eventContent.<path> deletes a dictionary entry
• insert first, insert last and sort by <property> [ascending|descending] in a children block control where new children are placed
• Diagnostics PLAY0956 to PLAY0963 for misplaced or invalid dictionary keys, remove lines and children ordering, reported alike by the C# and TypeScript compilers and the editor
• Semantic model version 43 executes set once and ordered children in specifications

Changed

• clear on a dictionary entry is now an error that points to remove