diff options
Diffstat (limited to 'nixpkgs/lib/path/README.md')
| -rw-r--r-- | nixpkgs/lib/path/README.md | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/nixpkgs/lib/path/README.md b/nixpkgs/lib/path/README.md index 87e552d120d7..89eec18b1130 100644 --- a/nixpkgs/lib/path/README.md +++ b/nixpkgs/lib/path/README.md @@ -187,6 +187,27 @@ Decision: All functions remove trailing slashes in their results. </details> +### Prefer returning subpaths over components +[subpath-preference]: #prefer-returning-subpaths-over-components + +Observing: Functions could return subpaths or lists of path component strings. + +Considering: Subpaths are used as inputs for some functions. Using them for outputs, too, makes the library more consistent and composable. + +Decision: Subpaths should be preferred over list of path component strings. + +<details> +<summary>Arguments</summary> + +- (+) It is consistent with functions accepting subpaths, making the library more composable +- (-) It is less efficient when the components are needed, because after creating the normalised subpath string, it will have to be parsed into components again + - (+) If necessary, we can still make it faster by adding builtins to Nix + - (+) Alternatively if necessary, versions of these functions that return components could later still be introduced. +- (+) It makes the path library simpler because there's only two types (paths and subpaths). Only `lib.path.subpath.components` can be used to get a list of components. + And once we have a list of component strings, `lib.lists` and `lib.strings` can be used to operate on them. + For completeness, `lib.path.subpath.join` allows converting the list of components back to a subpath. +</details> + ## Other implementations and references - [Rust](https://doc.rust-lang.org/std/path/struct.Path.html) |