From f1a9f7dd23833528eefa822931b1727ec0df9f1f Mon Sep 17 00:00:00 2001
From: lifning <>
Date: Sun, 17 Oct 2021 21:56:53 -0700
Subject: [PATCH] add a non-mut version, component_ref

---
 ferretro_components/src/base/mod.rs | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/ferretro_components/src/base/mod.rs b/ferretro_components/src/base/mod.rs
index f464c2c..96f6693 100644
--- a/ferretro_components/src/base/mod.rs
+++ b/ferretro_components/src/base/mod.rs
@@ -143,11 +143,21 @@ impl RetroComponentBase {
         Ok(RetroComponentId(self.components.len() - 1))
     }
 
+    pub fn component_ref<T: RetroComponent>(&self, id: RetroComponentId) -> Result<&T> {
+        self.component_ptr(id)
+            .map(|x| unsafe { &*x })
+    }
+
     pub fn component_mut<T: RetroComponent>(&mut self, id: RetroComponentId) -> Result<&mut T> {
+        self.component_ptr(id)
+            .map(|x| unsafe { &mut *x })
+    }
+
+    fn component_ptr<T: RetroComponent>(&self, id: RetroComponentId) -> Result<*mut T> {
         let (comp_type, comp_ptr) = self.component_ptrs.get(id.0)
             .ok_or_else(|| format!("Invalid ID given to component_mut: {:?}", id))?;
         if *comp_type == TypeId::of::<T>() {
-            Ok(unsafe { &mut *(*comp_ptr as *mut T) })
+            Ok(*comp_ptr as *mut T)
         } else {
             Err(format!(
                 "Invalid downcast for {:?}: {:?} != {:?}",