diff --git a/src/nix/flake.md b/src/nix/flake.md index f08648417..d8b5bf435 100644 --- a/src/nix/flake.md +++ b/src/nix/flake.md @@ -98,7 +98,15 @@ Here are some examples of flake references in their URL-like representation: ## Path-like syntax -Flakes corresponding to a local path can also be referred to by a direct path reference, either `/absolute/path/to/the/flake` or `./relative/path/to/the/flake` (note that the leading `./` is mandatory for relative paths to avoid any ambiguity). +Flakes corresponding to a local path can also be referred to by a direct +path reference, either `/absolute/path/to/the/flake` or`./relative/path/to/the/flake`. +Note that the leading `./` is mandatory for relative paths. If it is +omitted, the path will be interpreted as [URL-like syntax](#url-like-syntax), +which will cause error messages like this: + +```console +error: cannot find flake 'flake:relative/path/to/the/flake' in the flake registries +``` The semantic of such a path is as follows: @@ -153,18 +161,39 @@ can occur in *locked* flake references and are available to Nix code: Currently the `type` attribute can be one of the following: -* `path`: arbitrary local directories, or local Git trees. The - required attribute `path` specifies the path of the flake. The URL - form is +* `indirect`: *The default*. Indirection through the flake registry. + These have the form ``` - [path:](\?(/(/rev)?)? ``` - where *path* is an absolute path. + These perform a lookup of `` in the flake registry. For + example, `nixpkgs` and `nixpkgs/release-20.09` are indirect flake + references. The specified `rev` and/or `ref` are merged with the + entry in the registry; see [nix registry](./nix3-registry.md) for + details. - *path* must be a directory in the file system containing a file - named `flake.nix`. + For example, these are valid indirect flake references: + + * `nixpkgs` + * `nixpkgs/nixos-unstable` + * `nixpkgs/a3a3dda3bacf61e8a39258a0ed9c924eeca8e293` + * `nixpkgs/nixos-unstable/a3a3dda3bacf61e8a39258a0ed9c924eeca8e293` + * `sub/dir` (if a flake named `sub` is in the registry) + +* `path`: arbitrary local directories. The required attribute `path` + specifies the path of the flake. The URL form is + + ``` + path:(\?)? + ``` + + where *path* is an absolute path to a directory in the file system + containing a file named `flake.nix`. + + If the flake at *path* is not inside a git repository, the `path:` + prefix is implied and can be omitted. *path* generally must be an absolute path. However, on the command line, it can be a relative path (e.g. `.` or `./foo`) which is @@ -173,20 +202,24 @@ Currently the `type` attribute can be one of the following: (e.g. `nixpkgs` is a registry lookup; `./nixpkgs` is a relative path). + For example, these are valid path flake references: + + * `path:/home/user/sub/dir` + * `/home/user/sub/dir` (if `dir/flake.nix` is *not* in a git repository) + * `./sub/dir` (when used on the command line and `dir/flake.nix` is *not* in a git repository) + * `git`: Git repositories. The location of the repository is specified by the attribute `url`. They have the URL form ``` - git(+http|+https|+ssh|+git|+file|):(//)?(\?)? + git(+http|+https|+ssh|+git|+file):(//)?(\?)? ``` - or - - ``` - @: - ``` + If *path* starts with `/` (or `./` when used as an argument on the + command line) and is a local path to a git repository, the leading + `git:` or `+file` prefixes are implied and can be omitted. The `ref` attribute defaults to resolving the `HEAD` reference. @@ -203,6 +236,9 @@ Currently the `type` attribute can be one of the following: For example, the following are valid Git flake references: + * `git:/home/user/sub/dir` + * `/home/user/sub/dir` (if `dir/flake.nix` is in a git repository) + * `./sub/dir` (when used on the command line and `dir/flake.nix` is in a git repository) * `git+https://example.org/my/repo` * `git+https://example.org/my/repo?dir=flake1` * `git+ssh://git@github.com/NixOS/nix?ref=v1.2.3` @@ -324,19 +360,6 @@ Currently the `type` attribute can be one of the following: * `sourcehut:~misterio/nix-colors/182b4b8709b8ffe4e9774a4c5d6877bf6bb9a21c` * `sourcehut:~misterio/nix-colors/21c1a380a6915d890d408e9f22203436a35bb2de?host=hg.sr.ht` -* `indirect`: Indirections through the flake registry. These have the - form - - ``` - [flake:](/(/rev)?)? - ``` - - These perform a lookup of `` in the flake registry. For - example, `nixpkgs` and `nixpkgs/release-20.09` are indirect flake - references. The specified `rev` and/or `ref` are merged with the - entry in the registry; see [nix registry](./nix3-registry.md) for - details. - # Flake format As an example, here is a simple `flake.nix` that depends on the