From cb41f1c4a747f0dfcde69796812f798f9c868578 Mon Sep 17 00:00:00 2001
From: Colby Klein <shakesoda@gmail.com>
Date: Wed, 19 Aug 2015 14:30:48 -0700
Subject: [PATCH] Don't explode if the module has been hot reloaded.

Argh, struct redefinition errors. I'm glad that you can pcall this at
least.
---
 modules/vec2.lua | 12 +++++++++---
 modules/vec3.lua | 12 +++++++++---
 2 files changed, 18 insertions(+), 6 deletions(-)

diff --git a/modules/vec2.lua b/modules/vec2.lua
index a954829..7df0a99 100644
--- a/modules/vec2.lua
+++ b/modules/vec2.lua
@@ -33,11 +33,17 @@ vector.__index = vector
 -- Courtesy of slime
 local hasffi, ffi = pcall(require, "ffi")
 local jitenabled = jit and jit.status() or false
+local hot_loaded = false
 local new, isvector
 
 if hasffi and jitenabled then
-	ffi.cdef "struct cpml_vec2 { double x, y; };"
-	new = ffi.typeof("struct cpml_vec2")
+	xpcall(function()
+		hot_loaded = true
+		new = ffi.typeof("struct cpml_vec2")
+	end, function()
+		ffi.cdef "struct cpml_vec2 { double x, y; };"
+		new = ffi.typeof("struct cpml_vec2")
+	end)
 	function isvector(v)
 		return ffi.istype(new, v)
 	end
@@ -198,7 +204,7 @@ function vector:trim(maxLen)
 	return self:clone():trim_inplace(maxLen)
 end
 
-if hasffi and jitenabled then
+if hasffi and jitenabled and not hot_loaded then
 	ffi.metatype(new, vector)
 end
 
diff --git a/modules/vec3.lua b/modules/vec3.lua
index 6127371..3b04efa 100644
--- a/modules/vec3.lua
+++ b/modules/vec3.lua
@@ -37,11 +37,17 @@ vector.__index = vector
 -- Courtesy of slime
 local hasffi, ffi = pcall(require, "ffi")
 local jitenabled = jit and jit.status() or false
+local hot_loaded = false
 local new, isvector
 
 if hasffi and jitenabled then
-	ffi.cdef "struct cpml_vec3 { double x, y, z; };"
-	new = ffi.typeof("struct cpml_vec3")
+	xpcall(function()
+		hot_loaded = true
+		new = ffi.typeof("struct cpml_vec3")
+	end, function()
+		ffi.cdef "struct cpml_vec3 { double x, y, z; };"
+		new = ffi.typeof("struct cpml_vec3")
+	end)
 	function isvector(v)
 		return ffi.istype(new, v) or type(v.x and v.y and v.z) == "number"
 	end
@@ -248,7 +254,7 @@ function vector.lerp(a, b, s)
 	return a + s * (b - a)
 end
 
-if hasffi and jitenabled then
+if hasffi and jitenabled and not hot_loaded then
 	ffi.metatype(new, vector)
 end