This is an implementation of org-babel-tangle
in Nix.
Given an Org string, it extracts the contents of source blocks of a particular language.
talyz/fromElisp provides support for Org, and it is also part of emacs-overlay, which apparently is used by many people for their own configs. However, I wanted to experiment with more advanced features such as excluding archived entries, and I wasn’t sure if I could mix that with their code base. I needed the feature in my own project, and I wanted to put it under my control, so I wrote it from scratch.
Import the flake.
This function takes an Org string and returns its source blocks.
Example:
let
tangle = lib.tangleOrgBabel {
languages = [ "emacs-lisp" ];
};
in
# Return a string
tangle (builtins.readFile ./config.org)
Arguments:
- An attribute set of options.
- An Org input string.
Similar to tangleOrgBabel
, but this function takes a file as an argument and writes the output to a file.
Example:
# Write to a file
let
pkgs = import nixpkgs {
inherit system;
overlays = [
org-babel.overlay
];
};
in
pkgs.tangleOrgBabelFile "init.el" ./config.org {
languages = [ "emacs-lisp" ];
}
Note that this function is provided in the overlay of the flake.
Arguments:
- A string for the derivation name.
- An input file path.
- An attribute set of options.
Example:
{
languages = [ "emacs-lisp" "elisp" ];
}
Default: [ "emacs-lisp" "elisp" ]
You can transform the input by specifying processLines
option.
It must be a function that takes a list of strings and returns a list of strings.
This library also contains excludeHeadlines
function which can be used to exclude subtrees according to a predicate on the headline text, so you can use it in the option.
Example:
{
# Exclude archived subtrees
processLines = excludeHeadlines (matchOrgTag "ARCHIVE");
}
You can use the following predicates from this library:
- tag
- Returns true if the headline matches a tag given as the argument. The argument must be a string.
- headlineText
- Returns true if the headline matches the text given as the argument. The argument must be a string.