Improved README and examples, added nix flake

.github/workflows/tests-nix.yaml

@@ -0,0 +1,30 @@
+on: 
+    pull_request:
+    workflow_dispatch:
+
+  # this cancels workflows currently in progress if you start a new one
+concurrency:
+    group: ${{ github.workflow }}-${{ github.ref }}
+    cancel-in-progress: true
+
+jobs:  
+    test-examples-nix:
+      runs-on: [ubuntu-22.04]
+      steps:
+        - uses: actions/checkout@v3
+
+        # install nix
+        - uses: cachix/install-nix-action@v23
+          with:
+            nix_path: nixpkgs=channel:nixos-unstable
+
+        # Run all tests 
+        - name: Run all tests
+          run: nix develop -c sh -c 'export ROC=roc && ./ci/all_tests.sh'
+
+        - name: Run all tests and capture output to check for crash later
+          run: nix develop -c sh -c 'export ROC=roc && ./ci/all_tests.sh 2>&1 | tee all_tests_output.log'
+
+        # Workaround for https://github.com/roc-lang/roc/issues/6688
+        - name: Check if crash occurred
+          run: grep -qv "crashed" all_tests_output.log

.github/workflows/tests.yaml

@@ -9,8 +9,8 @@ concurrency:
 
 jobs:
 
-  test-examples:
-    runs-on: [ubuntu-20.04]
+  test-examples-ubuntu:
+    runs-on: [ubuntu-22.04]
     steps:
       - uses: actions/checkout@v3
 

.gitignore

@@ -1,7 +1,7 @@
 
 # Ignore the example binaries
-examples/simple
-examples/visualWidth
+examples/nrOfCodePoints
+examples/getVisualWidth
 example/splitGraphemes
 
 # Ignore the generated files

README.md

@@ -1,3 +1,12 @@
-# Work in progress!
+Convenient functions for working with unicode.
 
-Someday this will be a useful collection of Unicode operations, but for right now it's extremely WIP.
+⚠️ This package has only gone through limited testing. [Make an issue](https://github.com/roc-lang/unicode/issues) when you hit a bug.
+
+:eyes: [**examples**](https://github.com/roc-lang/unicode/tree/main/examples)
+
+:book: **documentation**: TODO
+
+
+## Learning about Unicode
+
+The string/unicode rabbit hole goes deep, we have a [good overview](https://www.roc-lang.org/builtins/Str) (scroll to the unicode section).

examples/visualWidth.roc → examples/getVisualWidth.roc

@@ -8,17 +8,18 @@ import unicode.CodePoint
 
 word = "世界"
 
-visualWidth : Result U32 CodePoint.Utf8ParseErr
-visualWidth =
-    word
+## Get the display width (in amount of characters) of a Str
+getVisualWidth : Str -> Result U32 CodePoint.Utf8ParseErr
+getVisualWidth = \str ->
+    str
     |> Str.toUtf8
     |> CodePoint.parseUtf8
     |> Result.map (\lst -> List.map lst CodePoint.visualWidth)
     |> Result.map List.sum
 
 main =
-    when visualWidth is
+    when (getVisualWidth word) is
         Ok width -> Stdout.line "\n\nThe word $(word) will be displayed with the width of $(Num.toStr width) characters on most UIs.\n\n"
         Err _ -> crash "ERROR: Unable to parse $(word)!"
 
-expect visualWidth == Ok 4
+expect (getVisualWidth word) == Ok 4

examples/nrOfCodePoints.roc

@@ -0,0 +1,24 @@
+app [main] {
+    pf: platform "https://github.com/roc-lang/basic-cli/releases/download/0.11.0/SY4WWMhWQ9NvQgvIthcv15AUeA7rAIJHAHgiaSHGhdY.tar.br",
+    unicode: "../package/main.roc", # use release URL (ends in tar.br) for local example, see github.com/roc/unicode/releases
+}
+
+import pf.Stdout
+import pf.Task
+import unicode.CodePoint exposing [Utf8ParseErr]
+
+## Get the number of code points for a given Str
+nrOfCodePoints : Str -> Result U64 Utf8ParseErr
+nrOfCodePoints = \str ->
+    str |> Str.toUtf8 |> CodePoint.parseUtf8 |> Result.map List.len
+
+main =
+    word = "ẇ͓̞͒͟͡ǫ̠̠̉̏͠͡ͅr̬̺͚̍͛̔͒͢d̠͎̗̳͇͆̋̊͂͐"
+
+    when nrOfCodePoints word is
+        Ok nr ->
+            Stdout.line "String \"$(word)\" consists of $(Num.toStr nr) code points."
+
+        Err _ ->
+            Task.err (Exit 1 "Failed to parse string $(word) as Utf8.")
+

flake.nix

@@ -0,0 +1,39 @@
+{
+  description = "Unicode package devShell flake";
+
+  inputs = {
+    roc.url = "github:roc-lang/roc";
+    nixpkgs.follows = "roc/nixpkgs";
+
+    # to easily make configs for multiple architectures
+    flake-utils.url = "github:numtide/flake-utils";
+  };
+
+  outputs = { self, nixpkgs, flake-utils, roc }:
+    let supportedSystems = [ "x86_64-linux" "x86_64-darwin" "aarch64-darwin" "aarch64-linux" ];
+    in flake-utils.lib.eachSystem supportedSystems (system:
+      let
+        pkgs = import nixpkgs { inherit system; };
+        rocPkgs = roc.packages.${system};
+
+        linuxInputs = with pkgs;
+          lib.optionals stdenv.isLinux [
+          ];
+
+        darwinInputs = with pkgs;
+          lib.optionals stdenv.isDarwin
+          (with pkgs.darwin.apple_sdk.frameworks; [
+          ]);
+
+        sharedInputs = (with pkgs; [
+          rocPkgs.cli
+        ]);
+      in {
+
+        devShell = pkgs.mkShell {
+          buildInputs = sharedInputs ++ darwinInputs ++ linuxInputs;
+        };
+
+        formatter = pkgs.nixpkgs-fmt;
+      });
+}