1 files changed, 149 insertions, 0 deletions
diff --git a/modules/default.nix b/modules/default.nix
new file mode 100644
index 0000000..fbe500d
--- /dev/null
+++ b/modules/default.nix
@@ -0,0 +1,149 @@
+{ config, lib, pkgs, ... }:
+
+with lib;
+let cfg = config;
+in {
+  imports =
+    [ ./coq.nix ./golang.nix ./latex.nix ./nix.nix ./python.nix ./ocaml.nix ];
+
+  options = {
+    # Inputs
+    inputsFrom = mkOption {
+      type = types.listOf types.package;
+      default = [ ];
+      description = ''
+        The list of derivations whose inputs will be made available to the environment.
+      '';
+      example = literalExample ''
+        [ pkgs.python3 ]
+      '';
+    };
+    buildInputs = mkOption {
+      type = types.listOf types.package;
+      default = [ ];
+      description = ''
+        The list of derivations which will be made available to the environment.
+      '';
+      example = literalExample ''
+        [ pkgs.ocamlPackages.owl ]
+      '';
+    };
+    nativeBuildInputs = mkOption {
+      type = types.listOf types.package;
+      default = [ ];
+      description = ''
+        The list of derivations which will be made available to the environment at run-time.
+      '';
+      example = literalExample ''
+        [ pkgs.python3 ];
+      '';
+    };
+
+    # EnvVars
+    envVars = mkOption {
+      type = types.attrsOf (types.submodule {
+        options = {
+          reset = mkOption {
+            type = types.bool;
+            default = false;
+            description = ''
+              If `true`, reset the value of the variable before changing it.
+              If `false`, the new value is thus set as $VAR=$VAR:`config.envVars.VAR.value`.
+            '';
+          };
+          value = mkOption {
+            type = types.envVar;
+            default = "";
+            description = ''
+              The new value to give to the environment variable.
+            '';
+          };
+        };
+      });
+      default = { };
+      description = ''
+        Environment variables that will be made available to the environment.
+      '';
+      example = {
+        PATH = {
+          reset = true;
+          value = "~/.local/bin";
+        };
+      };
+    };
+    aliases = mkOption {
+      type = types.attrsOf types.str;
+      default = { };
+      description = ''
+        Aliases.
+        If direnv is enabled, they are installed as executables in
+        .direnv/aliases. They may then take arguments. This also means that
+        "recursive" aliases (e.g. ssh="export A=something ssh") will fail ; the
+        executable in the definition should be called by its full path (e.g.
+        $\{pkgs.openssh\}/bin/ssh). 
+      '';
+      example = literalExample ''
+        { zz = "ls -la"; };
+      '';
+    };
+
+    # Misc
+    ## Whether the shell is to be loaded by direnv
+    direnv.enable = mkEnableOption "direnv";
+
+    # Hooks
+    shellHook = mkOption {
+      type = types.lines;
+      default = "";
+      description = ''
+        Commands to run after initializing the environment.
+      '';
+      example = ''
+        alias ll="ls -l"
+        git status
+      '';
+    };
+    exitHook = mkOption {
+      type = types.lines;
+      default = "";
+      description = ''
+        Commands to run when exiting the shell.
+      '';
+      example = ''
+        git clean
+      '';
+    };
+  };
+
+  config.shellHook = concatStringsSep "\n" (
+    # Environment variables are declared in a shell hook because simply adding the
+    # top-level arguments of pkgs.mkShell ovewrites the old values of the
+    # variables, which may be a problem, for example for PATH.
+    (let
+      dollar = "$";
+      makeEnvVarCommand = name:
+        { reset, value }:
+        ''
+          export "${name}"=${
+            optionalString (!reset) (''"${dollar}${name}":'')
+          }"${value}"'';
+    in (attrValues (mapAttrs makeEnvVarCommand cfg.envVars)))
+    ++ (if cfg.direnv.enable then
+      (let
+        aliasDir = ''"$PWD"/.direnv/aliases'';
+        makeAliasCommand = name: value:
+          let target = ''${aliasDir}/${name}'';
+          in ''
+            echo '#!${pkgs.bash}/bin/bash -e' > "${target}"
+            echo "${value}" >> "${target}"
+            chmod +x "${target}"
+          '';
+      in ([''
+        mkdir -p "${aliasDir}"
+        rm -f "${aliasDir}"/*
+        PATH="${aliasDir}":"$PATH" # $PATH has to come last for the alias to take effect
+      ''] ++ (attrValues (mapAttrs makeAliasCommand cfg.aliases))))
+    else
+      (let makeAliasCommand = name: value: ''alias "${name}"="${value}"'';
+      in (attrValues (mapAttrs makeAliasCommand cfg.aliases)))));
+}