System/ReleaseNotes/J903

J903 beta development started in Dec 2020, and 903-beta-a was released 21 Dec 2020.

Changes to the J engine

• List of problems fixed from J9.02

Summary of Changes to the J Language in the release

• New foreigns 9!:4 and 9!:5 support Nameref Caching, a way of avoiding name-lookup overhead especially useful when you have many locatives or long search paths.
• Old foreigns 2!:2 and 2!:3 are removed from the language

unreleased work in progress

• x ]\ y, x [\ y, and x ,\ y return a virtual result when x<0 and there is no shard
• f/ y faster on boolean arrays of rank >1 when f is a primitive logical operation
• +/ y rewritten for boolean y, faster
• special code for x f/@:g y with atomic f & g rewritten. Most special cases removed, as they are no longer faster than the normal code. Special code is used only when g cannot be executed in place.
• New foreigns 9!:4 and 9!:5 support nameref caching, a way of avoiding name-lookup overhead especially useful when you have many locatives or long search paths. Put ". :: 1:'9!:5(1)' at the top of your script to see if you can use the feature.
• Old foreigns 2!:2 and 2!:3 are removed from the language