nix-super/src/nix/edit.md

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Examples

• Open the Nix expression of the GNU Hello package:

  # nix edit nixpkgs#hello
  

• Get the filename and line number used by nix edit:

  # nix eval --raw nixpkgs#hello.meta.position
  /nix/store/fvafw0gvwayzdan642wrv84pzm5bgpmy-source/pkgs/applications/misc/hello/default.nix:15
  

Description

This command opens the Nix expression of a derivation in an editor. The filename and line number of the derivation are taken from its meta.position attribute. Nixpkgs' stdenv.mkDerivation sets this attribute to the location of the definition of the meta.description, version or name derivation attributes.

The editor to invoke is specified by the EDITOR environment variable. It defaults to cat. If the editor is emacs, nano or vim, it is passed the line number of the derivation using the argument +<lineno>.

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