This adds support for (limited) mutable variables. Mutable variables are created with mut much the same way immutable variables are made with let.
Mutable variables allow mutation via the assignment operator (=).
❯ mut x = 100
❯ $x = 200
❯ print $x
200
Mutable variables are limited in that they're only tended to be used in the local code block. Trying to capture a local variable will result in an error:
❯ mut x = 123; {|| $x }
Error: nu::parser::expected_keyword (link)
× Capture of mutable variable.
The intent of this limitation is to reduce some of the issues with mutable variables in general: namely they make code that's harder to reason about. By reducing the scope that a mutable variable can be used it, we can help create local reasoning about them.
Mutation can occur with fields as well, as in this case:
❯ mut y = {abc: 123}
❯ $y.abc = 456
❯ $y
On a historical note: mutable variables are something that we resisted for quite a long time, leaning as much as we could on the functional style of pipelines and dataflow. That said, we've watched folks struggle to work with reduce as an approximation for patterns that would be trivial to express with local mutation. With that in mind, we're leaning towards the happy path.
- Custom commands are true for builtin and custom
- Add classification as external command
- Specify wildcard in keyword: keyword is true for builtin and keyword
* Add failing test that list of ints and floats is List<Number>
* Start defining subtype relation
* Make it possible to declare input and output types for commands
- Enforce them in tests
* Declare input and output types of commands
* Add formatted signatures to `help commands` table
* Revert SyntaxShape::Table -> Type::Table change
* Revert unnecessary derive(Hash) on SyntaxShape
Co-authored-by: JT <547158+jntrnr@users.noreply.github.com>
* New "display_output" hook.
* Fix unrelated "clippy" complaint in nu-tables crate.
* Fix code-formattng and style issues in "display_output" hook
* Enhance eval_hook to return PipelineData.
This allows a hook (including display_output) to return a value.
Co-authored-by: JT <547158+jntrnr@users.noreply.github.com>
* Add support to render right prompt on last line of the prompt
* reset reedline to main branch
* update reedline to fix right prompt to be rendered correctly
* reset reedline to main branch again
* Revert "Revert "Try again: in unix like system, set foreground process while running external command (#6273)" (#6542)"
This reverts commit 2bb367f570.
* Make foreground job control hopefully work correctly
These changes are mostly inspired by the glibc manual.
* Fix typo in external command description
* Only restore tty control to shell when no fg procs are left; reuse pgrp
* Rework terminal acquirement code to be like fish
Co-authored-by: Darren Schroeder <343840+fdncred@users.noreply.github.com>
* remove export_env command
* remove several export env usage in test code
* adjust hiding relative test case
* fix clippy
* adjust tests
* update tests
* unignore these tests to expose ut failed
* using `use` instead of `overlay use` in some tests
* Revert "using `use` instead of `overlay use` in some tests"
This reverts commit 2ae24b24c3.
* Revert "adjust hiding relative test case"
This reverts commit 4369af6d05.
* Bring back module example
* Revert "update tests"
This reverts commit 6ae94ef513.
* Fix tests
* "Fix" a test
* Remove remaining deprecated env functionality
* Re-enable environment hiding for `hide`
To not break virtualenv since the overlay update is not merged yet
* Fix hiding env in `hide` and ignore some tests
Co-authored-by: kubouch <kubouch@gmail.com>
* Copy lev_distance.rs from the rust compiler
* Minor changes to code from rust compiler
* "Did you mean" suggestions: test instrumented to generate markdown report
* Did you mean suggestions: delete test instrumentation
* Fix tests
* Fix test
`foo` has a genuine match: `for`
* Improve tests
* Add source-env test for dynamic path
* Use correct module ID for env overlay imports
* Remove parser check from "overlay list"
It would cause unnecessary errors from some inner scope if some
overlay module was also defined in some inner scope.
* Restore Cargo.lock back
* Remove comments
* add new function to remove data at a cellpath; allow reject to use cellpath
* add tests
* fmt
* fix clippt
* get it working properly with lists of records
* fix clippy, hopefully
* fix clippy, hopefully 2
* start working on source-env
* WIP
* Get most tests working, still one to go
* Fix file-relative paths; Report parser error
* Fix merge conflicts; Restore source as deprecated
* Tests: Use source-env; Remove redundant tests
* Fmt
* Respect hidden env vars
* Fix file-relative eval for source-env
* Add file-relative eval to "overlay use"
* Use FILE_PWD only in source-env and "overlay use"
* Ignore new tests for now
This will be another issue
* Throw an error if setting FILE_PWD manually
* Fix source-related test failures
* Fix nu-check to respect FILE_PWD
* Fix corrupted spans in source-env shell errors
* Fix up some references to old source
* Remove deprecation message
* Re-introduce deleted tests
Co-authored-by: kubouch <kubouch@gmail.com>
