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.
* 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>
* make format filesize more flexible
* make code simpler
* finish refactor on bytes commands
* finish refactor on str commands
* fimplify code
* rename from column_paths to cell_paths
* Initialize join.rs as a copy of collect.rs
* Evolve StrCollect into StrJoin
* Replace 'str collect' with 'str join' everywhere
git ls-files | lines | par-each { |it| sed -i 's,str collect,str join,g' $it }
* Deprecate 'str collect'
* Revert "Deprecate 'str collect'"
This reverts commit 959d14203e.
* Change `str collect` help message to say that it is deprecated
We cannot remove `str collect` currently (i.e. via
`nu_protocol::ShellError::DeprecatedCommand` since a prominent project
uses the API:
b85542c31c/src/virtualenv/activation/nushell/activate.nu (L43)
* Test commands for proper names and search terms
Assert that the `Command.name()` is equal to `Signature.name`
Check that search terms are not just substrings of the command name as
they would not help finding the command.
* Clean up search terms
Remove redundant terms that just replicate the command name.
Try to eliminate substring between search terms, clean up where
necessary.
For instance,
```
echo 'abcdefghijklmnopqrstuvwxyz' | hash sha256 --binary
```
Will returns the hash as a binary value instead of a hexadecimaly encoded string.
* feat: deprecate `hash base64` command
* feat: extend `decode` and `encode` command families
This commit
- Adds `encode` command family
- Backports `hash base64` features to `encode base64` and `decode base64` subcommands.
- Refactors code a bit and extends tests for encodings
- `decode base64` returns a binary `Value` (that may be decoded into a string using `decode` command)
* feat: add `--binary(-b)` flag to `decode base64`
Default output type is now string, but binary can be requested using this new flag.
* Initial implementation of ordered call args
* Run cargo fmt
* Fix some clippy lints
* Add positional len and nth
* Cargo fmt
* Remove more old nth calls
* Good ole rustfmt
* Add named len
Co-authored-by: Hristo Filaretov <h.filaretov@protonmail.com>
