From fd8330cca372701a0cb39e8d4e2585b0f8ee1eb6 Mon Sep 17 00:00:00 2001
From: Yuichi Nishiwaki <yuichi.nishiwaki@gmail.com>
Date: Sun, 27 Jul 2014 13:57:15 +0900
Subject: [PATCH] add eval error handling

---
 src/eval.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/eval.c b/src/eval.c
index 579caa81..24807115 100644
--- a/src/eval.c
+++ b/src/eval.c
@@ -19,10 +19,15 @@ static pic_value
 pic_eval_eval(pic_state *pic)
 {
   pic_value program, spec;
+  struct pic_lib *lib;
 
   pic_get_args(pic, "oo", &program, &spec);
 
-  return pic_eval(pic, program, pic_find_library(pic, spec));
+  lib = pic_find_library(pic, spec);
+  if (lib == NULL) {
+    pic_errorf(pic, "no library found: ~s", spec);
+  }
+  return pic_eval(pic, program, lib);
 }
 
 void