Elvish 0.15.0 Release Notes

Version 0.15.0 has been released on 2021-01-30, 6 months after 0.14.0, bringing many new features and bugfixes.

As usual, prebuilt binaries are offered for most common platforms.

Breaking changes

  • Builtin functions and subnamespaces of edit: are now read-only.

  • 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.

  • The -source command now runs in a temporary namespace and can no longer affect the local scope of its caller.

  • Key modifiers are no longer case insensitive. For example, Alt is still recognized but alt is not. This makes key modifier parsing consistent with key names. See #1163.

Deprecated features

Deprecated features will be removed in 0.16.0.

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

  • Using the syntax of temporary assignment (var=value) for non-temporary assignment is now deprecated. The syntax is still valid for temporary assignment. For example, using foo=bar as a standalone command is deprecated, but using it as part of command, like foo=bar ls, is not deprecated.

  • 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 undocumented esleep command is now deprecated. Use sleep instead.

  • The eval-symlinks command is deprecated. Use path:eval-symlinks instead.

  • The path-abs command is deprecated. Use path:abs instead.

  • The path-base command is deprecated. Use path:base instead.

  • The path-clean command is deprecated. Use path:clean instead.

  • The path-dir command is deprecated. Use path:dir instead.

  • The path-ext command is deprecated. Use path:ext instead.

  • The -is-dir command is deprecated. Use path:is-dir instead.

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

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

  • The mechanism of assigning to $-exports- in rc.elv to export variables to the REPL namespace is deprecated. Use edit:add-vars instead.

Notable new features

New features in the language:

  • A new var special command can be used to explicitly declare variables, and optionally assign them initial values.

  • A new set special command can be used to set the values of variables or elements.

  • Slice indices 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.

  • Variables containing any character can now be assigned and used by quoting their name, for example 'name!' = foo; put $'name!'.

New features in the standard library:

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

  • A new sleep command.

  • A new path: module has been introduced for manipulating and testing filesystem paths.

  • A new deprecate command.

New features in the interactive editor:

  • The new commands edit:add-var and edit:add-vars provide an API for manipulating the REPL’s namespace from anywhere.

  • SGR escape sequences written from the prompt callback are now supported.

New features in the main program:

  • When using -compileonly to check Elvish sources that contain parse errors, Elvish will still try to compile the source code and print out compilation errors.

Notable bugfixes

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