From 77d4f098519d0bed5a19b4af81df62965ff24702 Mon Sep 17 00:00:00 2001
From: Roland Conybeare <rconybeare@gmail.com>
Date: Mon, 22 Sep 2025 12:44:01 -0400
Subject: [PATCH] nix build: xo-expression: build+install docs + examples

---
 default.nix            |  2 +-
 pkgs/xo-expression.nix | 22 +++++++++++++++++-----
 2 files changed, 18 insertions(+), 6 deletions(-)

diff --git a/default.nix b/default.nix
index c4578f5b..2b867d10 100644
--- a/default.nix
+++ b/default.nix
@@ -77,7 +77,6 @@ let
 
       in
         {
-          xo-expression     = self.callPackage pkgs/xo-expression.nix     {};
           xo-tokenizer      = self.callPackage pkgs/xo-tokenizer.nix      { buildDocs = true; };
           xo-reader         = self.callPackage pkgs/xo-reader.nix         {};
 
@@ -130,6 +129,7 @@ let
             xo-pykalmanfilter = self.callPackage pkgs/xo-pykalmanfilter.nix {};
             #
 
+            xo-expression     = self.callPackage pkgs/xo-expression.nix     {                   buildExamples = true; };
             xo-pyexpression   = self.callPackage pkgs/xo-pyexpression.nix   {};
             xo-pyjit          = self.callPackage pkgs/xo-pyjit.nix          {};
             #
diff --git a/pkgs/xo-expression.nix b/pkgs/xo-expression.nix
index c311fd06..561f7bf3 100644
--- a/pkgs/xo-expression.nix
+++ b/pkgs/xo-expression.nix
@@ -1,8 +1,11 @@
 {
   # dependencies
-  stdenv, cmake, catch2,
+  lib, stdenv, cmake, catch2,
 
-  xo-cmake, xo-reflect,
+  xo-cmake, xo-reflect, xo-flatstring,
+
+  buildDocs ? false,
+  buildExamples ? false,
 } :
 
 stdenv.mkDerivation (finalattrs:
@@ -12,10 +15,19 @@ stdenv.mkDerivation (finalattrs:
 
     src = ../xo-expression;
 
-    cmakeFlags = ["-DCMAKE_MODULE_PATH=${xo-cmake}/share/cmake"];
+    cmakeFlags = ["-DCMAKE_MODULE_PATH=${xo-cmake}/share/cmake"]
+                 ++ lib.optionals buildExamples ["-DXO_ENABLE_EXAMPLES=on"];
+
+    inherit buildDocs;
+    inherit buildExamples;
+
     doCheck = true;
-    propagatedBuildInputs = [ xo-reflect ];
-    nativeBuildInputs = [ cmake catch2
+
+    propagatedBuildInputs = [ xo-reflect
+                              xo-flatstring
+                            ];
+    nativeBuildInputs = [ cmake
+                          catch2
                           xo-cmake
                         ];
   })