mirror of
https://github.com/nushell/nushell
synced 2024-12-28 14:03:09 +00:00
5ca9e12b7f
* Remove EOL whitespace in files other than docs * Break paragraphs into lines See http://rhodesmill.org/brandon/2012/one-sentence-per-line/ for the rationale * Fix various typos * Remove EOL whitespace in docs/commands/*.md
34 lines
No EOL
1.6 KiB
Markdown
34 lines
No EOL
1.6 KiB
Markdown
# nu-source
|
|
|
|
## Overview
|
|
|
|
The `nu-source` crate contains types and traits used for keeping track of _metadata_ about values being processed.
|
|
Nu uses `Tag`s to keep track of where a value came from, an `AnchorLocation`,
|
|
as well as positional information about the value, a `Span`.
|
|
An `AnchorLocation` can be a `Url`, `File`, or `Source` text that a value was parsed from.
|
|
The source `Text` is special in that it is a type similar to a `String` that comes with the ability to be cheaply cloned.
|
|
A `Span` keeps track of a value's `start` and `end` positions.
|
|
These types make up the metadata for a value and are wrapped up together in a `Tagged` struct,
|
|
which holds everything needed to track and locate a value.
|
|
|
|
|
|
Nu's metadata system can be seen when reporting errors.
|
|
In the following example Nu is able to report to the user where the typo of a column originated from.
|
|
|
|
```
|
|
1 | ls | get typ
|
|
| ^^^ did you mean 'type'?
|
|
```
|
|
|
|
In addition to metadata tracking, `nu-source` also contains types and traits
|
|
related to debugging, tracing, and formatting the metadata and values it processes.
|
|
|
|
## Other Resources
|
|
- [Nushell Github Project](https://github.com/nushell):
|
|
Contains all projects in the Nushell ecosystem such as the source code to Nushell as well as website and books.
|
|
- [Nushell Git Repository](https://github.com/nushell/nushell):
|
|
A direct link to the source git repository for Nushell
|
|
- [Nushell Contributor Book](https://github.com/nushell/contributor-book):
|
|
An overview of topics about Nushell to help you get started contributing to the project.
|
|
- [Discord Channel](https://discordapp.com/invite/NtAbbGn)
|
|
- [Twitter](https://twitter.com/nu_shell) |