overlays/eww: fix build error

overlays/default.nix

@@ -1,6 +1,6 @@
 builtins.map (path: import path) [
   ./discord.nix
-  #./eww.nix
+  ./eww.nix
   ./material-icons.nix
   ./picom.nix
   ./rofi.nix

overlays/eww.nix

@@ -1,6 +1,10 @@
 self: super: {
   eww = super.eww.overrideAttrs (old: rec {
-    # Use normal scroll events instead of smooth scroll ( due to https://bugzilla.gnome.org/show_bug.cgi?id=675959 )
+    patches = old.patches ++ [
-    patches = old.patches ++ [ ./patches/eww.patch ];
+      # Use normal scroll events instead of smooth scroll ( due to https://bugzilla.gnome.org/show_bug.cgi?id=675959 )
+      ./patches/eww.patch
+      # Backport https://github.com/elkowar/eww/pull/711
+      ./patches/eww-box.patch
+    ];
   });
 }

overlays/patches/eww-box.patch

@@ -0,0 +1,57 @@
+From fba770255dd72db8301b5f51ef50ab59e7746515 Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?=C3=A9clairevoyant?=
+ <848000+eclairevoyant@users.noreply.github.com>
+Date: Mon, 20 Mar 2023 07:40:36 -0400
+Subject: [PATCH] remove box_syntax (#711)
+
+Rust removed support for box_syntax in a recent nightly release :'(
+---
+ crates/eww/src/main.rs       | 1 -
+ crates/simplexpr/src/eval.rs | 8 ++++----
+ crates/simplexpr/src/lib.rs  | 1 -
+ 3 files changed, 4 insertions(+), 6 deletions(-)
+
+diff --git a/crates/eww/src/main.rs b/crates/eww/src/main.rs
+index 8e51a626..14bc8190 100644
+--- a/crates/eww/src/main.rs
++++ b/crates/eww/src/main.rs
+@@ -1,6 +1,5 @@
+ #![feature(trace_macros)]
+ #![feature(drain_filter)]
+-#![feature(box_syntax)]
+ #![feature(box_patterns)]
+ #![feature(slice_concat_trait)]
+ #![feature(try_blocks)]
+diff --git a/crates/simplexpr/src/eval.rs b/crates/simplexpr/src/eval.rs
+index d0b48115..76f811da 100644
+--- a/crates/simplexpr/src/eval.rs
++++ b/crates/simplexpr/src/eval.rs
+@@ -69,13 +69,13 @@ impl SimplExpr {
+     pub fn try_map_var_refs<E, F: Fn(Span, VarName) -> Result<SimplExpr, E> + Copy>(self, f: F) -> Result<Self, E> {
+         use SimplExpr::*;
+         Ok(match self {
+-            BinOp(span, box a, op, box b) => BinOp(span, box a.try_map_var_refs(f)?, op, box b.try_map_var_refs(f)?),
++            BinOp(span, box a, op, box b) => BinOp(span, Box::new(a.try_map_var_refs(f)?), op, Box::new(b.try_map_var_refs(f)?)),
+             Concat(span, elems) => Concat(span, elems.into_iter().map(|x| x.try_map_var_refs(f)).collect::<Result<_, _>>()?),
+-            UnaryOp(span, op, box a) => UnaryOp(span, op, box a.try_map_var_refs(f)?),
++            UnaryOp(span, op, box a) => UnaryOp(span, op, Box::new(a.try_map_var_refs(f)?)),
+             IfElse(span, box a, box b, box c) => {
+-                IfElse(span, box a.try_map_var_refs(f)?, box b.try_map_var_refs(f)?, box c.try_map_var_refs(f)?)
++                IfElse(span, Box::new(a.try_map_var_refs(f)?), Box::new(b.try_map_var_refs(f)?), Box::new(c.try_map_var_refs(f)?))
+             }
+-            JsonAccess(span, box a, box b) => JsonAccess(span, box a.try_map_var_refs(f)?, box b.try_map_var_refs(f)?),
++            JsonAccess(span, box a, box b) => JsonAccess(span, Box::new(a.try_map_var_refs(f)?), Box::new(b.try_map_var_refs(f)?)),
+             FunctionCall(span, name, args) => {
+                 FunctionCall(span, name, args.into_iter().map(|x| x.try_map_var_refs(f)).collect::<Result<_, _>>()?)
+             }
+diff --git a/crates/simplexpr/src/lib.rs b/crates/simplexpr/src/lib.rs
+index 205b2989..8a402877 100644
+--- a/crates/simplexpr/src/lib.rs
++++ b/crates/simplexpr/src/lib.rs
+@@ -1,6 +1,5 @@
+ #![feature(box_patterns)]
+ #![feature(pattern)]
+-#![feature(box_syntax)]
+ #![feature(try_blocks)]
+ #![feature(unwrap_infallible)]
+ #![feature(never_type)]