diff options
Diffstat (limited to 'infra/libkookie/nixpkgs/lib/fixed-points.nix')
| -rw-r--r-- | infra/libkookie/nixpkgs/lib/fixed-points.nix | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/infra/libkookie/nixpkgs/lib/fixed-points.nix b/infra/libkookie/nixpkgs/lib/fixed-points.nix index 968930526a63..f998bc74e1db 100644 --- a/infra/libkookie/nixpkgs/lib/fixed-points.nix +++ b/infra/libkookie/nixpkgs/lib/fixed-points.nix @@ -1,4 +1,4 @@ -{ ... }: +{ lib, ... }: rec { # Compute the fixed point of the given function `f`, which is usually an # attribute set that expects its final, non-recursive representation as an @@ -77,6 +77,15 @@ rec { super' = super // fApplied; in fApplied // g self super'; + # Compose several extending functions of the type expected by 'extends' into + # one where changes made in preceding functions are made available to + # subsequent ones. + # + # composeManyExtensions : [packageSet -> packageSet -> packageSet] -> packageSet -> packageSet -> packageSet + # ^final ^prev ^overrides ^final ^prev ^overrides + composeManyExtensions = + lib.foldr (x: y: composeExtensions x y) (self: super: {}); + # Create an overridable, recursive attribute set. For example: # # nix-repl> obj = makeExtensible (self: { }) |