elvish/NEXT-RELEASE.md

This is the draft release notes for 0.15.0, scheduled to be released on 2021-01-01.

Breaking changes

• Introspection for rest arguments has changed:

  • The rest argument is now contained in the arg-names field of a closure.

  • The rest-arg field now contains the index of the rest argument, instead of the name.

Deprecated features

The following deprecated features trigger a warning whenever the code is parsed or compiled, even if it is not executed:

• The chr command is now deprecated. Use str:from-codepoints instead.

• The ord command is now deprecated. Use str:to-codepoints instead.

• The has-prefix command is now deprecated. Use str:has-prefix instead.

• The has-suffix command is now deprecated. Use str:has-suffix instead.

• The -source command is now deprecated. Use eval instead.

The following deprecated features trigger a warning when the code is evaluated:

• Using : in slice indicies is deprecated. Use .. instead.

Notable new features

New features in the language:

• Slice indicies can now use .. for left-closed, right-open ranges, and ..= for closed ranges.

• Rest variables and rest arguments are no longer restricted to the last variable.

New features in the standard library:

• A new eval command supports evaluating a dynamic piece of code in a restricted namespace.

Notable bugfixes

• Using large lists that contain $nil no longer crashes Elvish.