parse/compile errors have better error messages

bin/moon

@@ -41,7 +41,16 @@ local new_arg = {
 	select(ind + 1, unpack(arg))
 }
 
-local chunk = moonscript.loadfile(script_fname)
+local chunk
+local passed, err = pcall(function()
+	chunk = moonscript.loadfile(script_fname)
+end)
+
+if not passed then
+	print(err)
+	os.exit()
+end
+
 getfenv(chunk).arg = new_arg
 
 local runner = coroutine.create(chunk)

moonscript/init.lua

@@ -27,7 +27,7 @@ to_lua = function(text)
   end
   local tree, err = parse.string(text)
   if not tree then
-    error("Parse error: " .. err, 2)
+    error(err, 2)
   end
   local code, ltable, pos = compile.tree(tree)
   if not code then
@@ -65,7 +65,12 @@ if not _G.moon_no_loader then
   init_loader()
 end
 loadstring = function(str, chunk_name)
-  local code, ltable = to_lua(str)
+  local passed, code, ltable = pcall(function()
+    return to_lua(str)
+  end)
+  if not passed then
+    error(chunk_name .. ": " .. code, 2)
+  end
   if chunk_name then
     line_tables[chunk_name] = ltable
   end

moonscript/init.moon

@@ -31,7 +31,7 @@ to_lua = (text) ->
 
   tree, err = parse.string text
   if not tree
-    error "Parse error: " .. err, 2
+    error err, 2
 
   code, ltable, pos = compile.tree tree
   if not code
@@ -63,7 +63,10 @@ init_loader = ->
 init_loader! if not _G.moon_no_loader
 
 loadstring = (str, chunk_name) ->
-  code, ltable = to_lua str
+  passed, code, ltable = pcall -> to_lua str
+  if not passed
+    error chunk_name .. ": " .. code, 2
+
   line_tables[chunk_name] = ltable if chunk_name
   lua.loadstring code, chunk_name or "=(moonscript.loadstring)"