forked from extern/nushell
d95375d494
* Resolve rebase artifacts * Remove leftover dependencies on removed feature * Remove unnecessary 'pub' * Start taking notes and fooling around * Split canonicalize to two versions; Add TODOs One that takes `relative_to` and one that doesn't. More TODO notes. * Merge absolutize to and rename resolve_dots * Add custom absolutize fn and use it in path expand * Convert a couple of dunce::canonicalize to ours * Update nu-path description * Replace all canonicalize with nu-path version * Remove leftover dunce dependencies * Fix broken autocd with trailing slash Trailing slash is preserved *only* in paths that do not contain "." or "..". This should be fixed in the future to cover all paths but for now it at least covers basic cases. * Use dunce::canonicalize for canonicalizing * Alow cd recovery from non-existent cwd * Disable removed canonicalize functionality tests Remove unused import * Break down nu-path into separate modules * Remove unused public imports * Remove abundant cow mapping * Fix clippy warning * Reformulate old canonicalize tests to expand_path They wouldn't work with the new canonicalize. * Canonicalize also ~ and ndots; Unify path joining Also, add doc comments in nu_path::expansions. * Add comment * Avoid expanding ndots if path is not valid UTF-8 With this change, no lossy path->string conversion should happen in the nu-path crate. * Fmt * Slight expand_tilde refactor; Add doc comments * Start nu-path integration tests * Add tests TODO * Fix docstring typo * Fix some doc strings * Add README for nu-path crate * Add a couple of canonicalize tests * Add nu-path integration tests * Add trim trailing slashes tests * Update nu-path dependency * Remove unused import * Regenerate lockfile |
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README.md |
Nu-Engine
Nu-engine handles most of the core logic of nushell. For example, engine handles: - Passing of data between commands - Evaluating a commands return values - Loading of user configurations
Top level introduction
The following topics shall give the reader a top level understanding how various topics are handled in nushell.
How are environment variables handled?
Environment variables (or short envs) are stored in the Scope
of the EvaluationContext
. That means that environment variables are scoped by default and we don't use std::env
to store envs (but make exceptions where convenient).
Nushell handles environment variables and their lifetime the following:
- At startup all existing environment variables are read and put into
Scope
. (Nushell reads existing environment variables platform independent by asking theHost
. They will most likely come fromstd::env::*
) - Envs can also be loaded from config files. Each loaded config produces a new
ScopeFrame
with the envs of the loaded config. - Nu-Script files and internal commands read and write env variables from / to the
Scope
. External scripts and binaries can't interact with theScope
. Therefore all env variables are read from theScope
and put into the external binaries environment-variables-memory area.