Merge pull request #6281 from JRMurr/nix-template-setup

Add install docs for nix + fix `nix run` for using the roc cli

flake.nix

@@ -27,11 +27,16 @@
   };
 
   outputs = { self, nixpkgs, rust-overlay, flake-utils, nixgl, ... }@inputs:
-    let supportedSystems = [ "x86_64-linux" "x86_64-darwin" "aarch64-darwin" "aarch64-linux" ];
-    in flake-utils.lib.eachSystem supportedSystems (system:
+    let
+      supportedSystems = [ "x86_64-linux" "x86_64-darwin" "aarch64-darwin" "aarch64-linux" ];
+
+      templates = import ./nix/templates { };
+    in
+    { inherit templates; } //
+    flake-utils.lib.eachSystem supportedSystems (system:
       let
         overlays = [ (import rust-overlay) ]
-          ++ (if system == "x86_64-linux" then [ nixgl.overlay ] else [ ]);
+        ++ (if system == "x86_64-linux" then [ nixgl.overlay ] else [ ]);
         pkgs = import nixpkgs { inherit system overlays; };
 
         rocBuild = import ./nix { inherit pkgs; };
@@ -105,7 +110,7 @@
 
         devShell = pkgs.mkShell {
           buildInputs = sharedInputs ++ sharedDevInputs ++ darwinInputs ++ darwinDevInputs ++ linuxDevInputs
-            ++ (if system == "x86_64-linux" then
+          ++ (if system == "x86_64-linux" then
             [ pkgs.nixgl.nixVulkanIntel ]
           else
             [ ]);
@@ -121,7 +126,7 @@
           LD_LIBRARY_PATH = with pkgs;
             lib.makeLibraryPath
               ([ pkg-config stdenv.cc.cc.lib libffi ncurses zlib ]
-                ++ linuxDevInputs);
+              ++ linuxDevInputs);
           NIXPKGS_ALLOW_UNFREE =
             1; # to run the GUI examples with NVIDIA's closed source drivers
 
@@ -143,5 +148,12 @@
           cli = rocBuild.roc-cli;
           lang-server = rocBuild.roc-lang-server;
         };
+
+        apps = {
+          default = {
+            type = "app";
+            program = "${rocBuild.roc-cli}/bin/roc";
+          };
+        };
       });
 }

getting_started/README.md

@@ -11,6 +11,7 @@ If you have a specific question, the [FAQ](../FAQ.md) might have an answer, alth
 ## Installation
 
 - [🐧 Linux x86_64](linux_x86_64.md)
+- [❄️ Nix Linux/MacOS](nix.md)
 - [🍏 MacOS Apple Silicon](macos_apple_silicon.md)
 - [🍏 MacOS x86_64](macos_x86_64.md)
 - [🟦 Windows](windows.md)

getting_started/nix.md

@@ -0,0 +1,48 @@
+## Try out
+
+To quickly try out roc without installing, use `nix run`:
+```shell
+nix run roc-lang/roc -- <roc args>
+# examples:
+# - nix run roc-lang/roc -- repl
+# - nix run roc-lang/roc -- dev main.roc
+```
+
+## Use with Flakes
+
+
+### Start your project with our template
+
+```shell
+# use the template in the current directory
+nix flake init --template github:roc-lang/roc#simple --refresh
+```
+
+### Add roc to existing flake
+```nix
+{
+    inputs = {
+        nixpkgs.url = "github:nixos/nixpkgs/nixos-unstable";
+        flake-utils.url = "github:numtide/flake-utils";
+        roc.url = "github:roc-lang/roc";
+    };
+
+    outputs = {nixpkgs, roc, flake-utils, ...}:
+        flake-utils.lib.eachDefaultSystem (system:
+            let
+                pkgs = import nixpkgs { inherit system; };
+                rocPkgs = roc.packages.${system};
+            in
+            {
+                devShells = {
+                    default = pkgs.mkShell {
+                        buildInputs = with pkgs;
+                        [
+                            rocPkgs.cli
+                        ];
+                    };
+                };
+            }
+        );
+}
+```

nix/builder.nix

@@ -3,6 +3,8 @@ let
   inherit (compile-deps) zigPkg llvmPkgs llvmVersion llvmMajorMinorStr glibcPath libGccSPath;
 
   subPackagePath = if subPackage != null then "crates/${subPackage}" else null;
+
+  mainBin = if subPackage == "lang_srv" then "roc_ls" else "roc";
 in
 rustPlatform.buildRustPackage {
   pname = "roc" + lib.optionalString (subPackage != null) "_${subPackage}";
@@ -84,4 +86,11 @@ rustPlatform.buildRustPackage {
         ${wrapRoc}
       fi
     '';
+
+  # https://ryantm.github.io/nixpkgs/stdenv/meta/
+  meta = {
+    homepage = "https://www.roc-lang.org/";
+    license = lib.licenses.upl;
+    mainProgram = mainBin;
+  };
 }

nix/templates/default.nix

@@ -0,0 +1,7 @@
+{ ... }: rec {
+  default = simple;
+  simple = {
+    description = "Basic flake with roc cli + lsp";
+    path = ./simple;
+  };
+}

nix/templates/simple/flake.nix

@@ -0,0 +1,38 @@
+{
+  description = "Roc flake template";
+
+  inputs = {
+    nixpkgs.url = "github:nixos/nixpkgs/nixos-unstable";
+    flake-utils.url = "github:numtide/flake-utils";
+    roc.url = "github:roc-lang/roc";
+  };
+
+  outputs = { self, nixpkgs, flake-utils, roc, ... }:
+    flake-utils.lib.eachDefaultSystem (system:
+      let
+        pkgs = import nixpkgs { inherit system; };
+
+        # see "packages =" in https://github.com/roc-lang/roc/blob/main/flake.nix
+        rocPkgs = roc.packages.${system};
+
+        rocFull = rocPkgs.full;
+
+      in
+      {
+        formatter = pkgs.nixpkgs-fmt;
+
+        devShells = {
+          default = pkgs.mkShell {
+            buildInputs = with pkgs;
+              [
+                rocFull # includes CLI
+              ];
+
+            # For vscode plugin https://github.com/ivan-demchenko/roc-vscode-unofficial
+            shellHook = ''
+              export ROC_LSP_PATH=${rocFull}/bin/roc_ls
+            '';
+          };
+        };
+      });
+}

www/content/install.md

@@ -5,7 +5,7 @@ Roc is a very young language with many incomplete features and known bugs. It do
 There are currently a few known OS-specific issues:
 * **macOS:** There are no known compatibility issues, but the compiler doesn't run as fast as it does on Linux or Windows, because we don't (yet) do our own linking like we do on those targets. (Linking works similarly on Linux and Windows, but the way macOS does it is both different and significantly more complicated.)
 * **Windows:** There are some known Windows-specific compiler bugs, and probably some other unknown ones because more people have tried out Roc on Mac and Linux than on Windows.
-* **Linux:** The nightlies are built with glibc, so they aren't usable on distros that don't use (dynamically linked) glibc, like Alpine or NixOS. In the future we plan to build Linux releases with [musl libc](https://wiki.musl-libc.org/) to address this, but this requires [building LLVM from source with musl](https://wiki.musl-libc.org/building-llvm.html).
+* **Linux:** The nightlies are built with glibc, so they aren't usable on distros that don't use glibc, like Alpine. In the future we plan to build Linux releases with [musl libc](https://wiki.musl-libc.org/) to address this, but this requires [building LLVM from source with musl](https://wiki.musl-libc.org/building-llvm.html).
 * **Other operating systems:** Roc has not been built on any other operating systems. [Building from source](https://github.com/roc-lang/roc/blob/main/BUILDING_FROM_SOURCE.md) on another OS might work, but you might very well be the first person ever to try it!
 
 ### [Getting Started](#getting-started) {#getting-started}
@@ -14,6 +14,7 @@ Here are some Getting Started guides for different operating systems:
 <!-- TODO detect current OS with browser and only show link for that, provide other button for others  -->
 
 - [Linux x86-64](https://github.com/roc-lang/roc/blob/main/getting_started/linux_x86_64.md)
+- [Nix Linux/MacOS](https://github.com/roc-lang/roc/blob/main/getting_started/nix.md)
 - [MacOS Apple Silicon](https://github.com/roc-lang/roc/blob/main/getting_started/macos_apple_silicon.md)
 - [MacOS x86-64](https://github.com/roc-lang/roc/blob/main/getting_started/macos_x86_64.md)
 - [Windows](https://github.com/roc-lang/roc/blob/main/getting_started/windows.md)