doc: build and deploy doc from Nix to GitHub Pages

.github/workflows/documentation.yml

@@ -0,0 +1,39 @@
+name: Documentation
+on:
+  push:
+    branches: [main]
+
+jobs:
+  doc:
+    name: Documentation
+    runs-on: ubuntu-22.04
+    steps:
+      - name: Install Nix
+        uses: cachix/install-nix-action@v25
+      - name: Cache Nix derivations
+        uses: DeterminateSystems/magic-nix-cache-action@v2
+      - uses: actions/checkout@v2
+      - name: Fetch all git history
+        run: git fetch --force --prune --tags --unshallow
+      - name: Build documentation
+        run: nix build .#workspace.doc
+      - name: Fix permissions
+        run: |
+          chmod -c -R +rX "_site/" | while read line; do
+            echo "::warning title=Invalid file permissions automatically fixed::$line"
+          done
+      - name: Upload Pages artifact
+        uses: actions/upload-pages-artifact@v2
+  doc-deploy:
+    needs: doc
+    permissions:
+      pages: write      # to deploy to Pages
+      id-token: write   # to verify the deployment originates from an appropriate source
+    environment:
+      name: github-pages
+      url: ${{ steps.deployment.outputs.page_url }}
+    runs-on: ubuntu-latest
+    steps:
+      - name: Deploy to GitHub Pages
+        id: deployment
+        uses: actions/deploy-pages@v4 # or specific "vX.X.X" version tag for this action

src/lib.rs

@@ -1,3 +1,4 @@
+#![doc = include_str!("../README.md")]
 use az::CastFrom;
 use num_traits::Zero;
 use simba::simd::{AutoSimd, SimdRealField, SimdValue};