add mix as a primitive (for nt bootstrap)

nt/primitives/mix/default.nix

@@ -0,0 +1,154 @@
+{this, ...}: let
+  inherit
+    (builtins)
+    attrNames
+    attrValues
+    hasAttr
+    listToAttrs
+    removeAttrs
+    ;
+
+  inherit
+    (this.util)
+    filterAttrs
+    hasInfix
+    mergeAttrsList
+    nameValuePair
+    projectOnto
+    removeSuffix
+    Wrap
+    ;
+
+  modNameFromPath = path: let
+    name = baseNameOf path |> removeSuffix ".nix";
+  in
+    assert (! hasInfix "." name)
+    || throw ''
+      Mix module ${path} has invalid name \"${name}\".
+      Module names must not contain the . (period) character.
+    ''; name;
+in rec {
+  # by default the imported module is given the basename of its path
+  # but you can set it manually by using the `mix.mod` function.
+  importMods = list: inputs:
+    list
+    |> map (path: nameValuePair (modNameFromPath path) (import path inputs))
+    |> listToAttrs;
+
+  importMergeMods = list: inputs:
+    list
+    |> map (path: (import path inputs))
+    |> mergeAttrsList;
+
+  # create a new and empty mixture
+  newMixture' = let
+    self = {
+      # trapdoor attribute
+      _' = {
+        path = [];
+        modName = null;
+      };
+    };
+  in
+    self;
+
+  # a splash of this, a splash of that ^_^
+  add = ingredients: mixture: let
+    sidedish = mergeAttrsList ingredients;
+  in
+    # bone apple tea ;-;
+    mixture // filterAttrs (x: _: ! hasAttr x mixture) sidedish;
+
+  newMixture = inputs: modBuilder: let
+    inputs' = removeAttrs inputs ["this"];
+    inputsWithThis = inputs' // {this = mixture;};
+
+    # mixture components are ordered based on shadowing
+    mixture =
+      inputs'
+      // importMods meta.submods.public inputsWithThis
+      // importMergeMods meta.includes.public inputsWithThis
+      // content;
+
+    # this = {
+    #   # trapdoor attribute
+    #   _' = {
+    #     path = [];
+    #   };
+    #   parent' = throw "Mix: The mixture's root module has no parent by definition.";
+    # };
+
+    # partition modAttrs' into metadata and content
+    modAttrs' = modBuilder mixture;
+    content = removeAttrs modAttrs' (attrNames meta);
+    # attributes expected by and that directly modify mix's behaviour
+    meta =
+      modAttrs'
+      |> projectOnto
+      {
+        includes = {
+          public = [];
+          private = [];
+          protected = [];
+        };
+        submods = {
+          public = [];
+          private = [];
+          protected = [];
+        };
+        options = Wrap {};
+        config = Wrap {};
+      };
+  in
+    mixture;
+
+  mkMod = mixture: modBuilder: let
+    # XXX: TODO
+    # modAttrs = modBuilder privateMixture;
+    modAttrs = modBuilder mixture;
+
+    # attributes expected by and that directly modify mix's behaviour
+    meta =
+      modAttrs
+      |> projectOnto
+      {
+        includes = {
+          public = [];
+          private = [];
+          protected = [];
+        };
+        submods = {
+          public = [];
+          private = [];
+          protected = [];
+        };
+        options = Wrap {};
+        config = Wrap {};
+      };
+
+    # XXX: TODO
+    # protectedMixture = add [public protected] mixture;
+    # privateMixture = add [private] protectedMixture;
+
+    mkInterface = name: mixture: base:
+      mergeAttrsList
+      (attrValues <| importMods meta.includes.${name} mixture)
+      ++ [
+        base
+        (importMods meta.submods.${name} mixture)
+      ];
+    # XXX: TODO
+    # NOTE: public submodules are still DESCENDENTS
+    # NOTE: and should be able to access protected values :)
+    # public = mkInterface "public" protectedMixture content;
+    # protected = mkInterface "protected" protectedMixture public;
+    # private = mkInterface "private" privateMixture protected;
+    content = throw "TODO";
+    public = mkInterface "public" mixture content;
+    protected = mkInterface "protected" mixture public;
+    private = mkInterface "private" mixture protected;
+  in
+    # XXX: TODO
+    # public;
+    modAttrs;
+}

nt/primitives/util/util.nix

@@ -2,6 +2,7 @@
 {...}: let
   inherit
     (builtins)
+    attrNames
     elem
     elemAt
     filter
@@ -10,8 +11,10 @@
     genList
     length
     mapAttrs
+    match
     partition
     removeAttrs
+    replaceStrings
     stringLength
     substring
     tail
@@ -97,6 +100,14 @@ in rec {
   stringInit = x: x |> stringTake 1;
   stringLast = x: stringElem (stringLength x - 1);
 
+  stringToCharacters = s: genList (p: substring p 1 s) (stringLength s);
+
+  escape = list: replaceStrings list (map (c: "\\${c}") list);
+  escapeRegex = escape (stringToCharacters "\\[{()^$?*+|.");
+
+  hasInfix = infix: content:
+    match ".*${escapeRegex infix}.*" "${content}" != null;
+
   countEvensLeq = n: n / 2;
   countOddsLeq = n: (n + 1) / 2;
 
@@ -151,4 +162,11 @@ in rec {
         |> filter (x: head x == name)
         |> map tail
         |> removeAttrsRec);
+
+  filterAttrs = pred: xs:
+    attrNames xs
+    |> filter (name: ! pred name xs.${name})
+    |> removeAttrs xs;
+
+  nameValuePair = name: value: {inherit name value;};
 }