migrate lib functions to lib/, remove extra overlays

Signed-off-by: ahuston-0 <aliceghuston@gmail.com>

lib/default.nix

@@ -0,0 +1,61 @@
+{ lib, ... }:
+{
+  # create rad-dev namespace for lib
+  rad-dev = rec {
+    # any(), but checks if any value in the list is true
+    #
+    # args:
+    # n: list of booleans
+    #
+    # type:
+    # anyBool:: [bool] -> bool
+    anyBool = lib.any (n: n);
+
+    # pulls a value out of an attrset and converts it to a list
+    #
+    # args:
+    # attr: attribute to search for in an attrset
+    # set: attrset to search
+    #
+    # type:
+    # mapGetAttr :: String -> Attrset -> [Any]
+    mapGetAttr = (attr: set: lib.mapAttrsToList (_: attrset: lib.getAttr attr attrset) set);
+
+    # gets list of files and directories inside of a directory
+    #
+    # args:
+    # base: base path to search
+    # dir: directory to get files from
+    #
+    # type:
+    # ls :: Path -> String -> [String]
+    ls = base: dir: lib.attrNames (builtins.readDir (base + "/${dir}"));
+
+    # gets list of directories inside of a given directory
+    #
+    # args:
+    # base: base path to search
+    # dir: directory to get files from
+    #
+    # type:
+    # lsdir :: Path -> String -> [String]
+    lsdir =
+      base: dir:
+      if (builtins.pathExists (base + "/${dir}")) then
+        (lib.attrNames (
+          lib.filterAttrs (path: type: type == "directory") (builtins.readDir (base + "/${dir}"))
+        ))
+      else
+        [ ];
+
+    # return full paths of all files in a directory
+    #
+    # args:
+    # base: base path to search
+    # dir: path to get files from
+    #
+    # type:
+    # fileList :: Path -> String -> [Path]
+    fileList = base: dir: map (file: base + "/${dir}/${file}") (ls base dir);
+  };
+}