From 486ec3ba9d91259426fd51c40e2d0523640d7326 Mon Sep 17 00:00:00 2001
From: Marvin Blum <marvin@marvinblum.de>
Date: Sun, 25 Oct 2015 17:03:21 +0100
Subject: [PATCH] Removed panic on "no tokens provided".

---
 README.md               | 4 ++--
 ToDo.md                 | 3 +++
 in/sub/empty.asl        | 0
 out/sub/empty.sqf       | 0
 src/asl/parser.go       | 4 +++-
 src/asl/parserHelper.go | 6 ++++--
 6 files changed, 12 insertions(+), 5 deletions(-)
 create mode 100644 in/sub/empty.asl
 create mode 100644 out/sub/empty.sqf

diff --git a/README.md b/README.md
index 3b44735..71554d2 100644
--- a/README.md
+++ b/README.md
@@ -28,8 +28,8 @@ asl [-v|-r|-pretty|--help] <input directory> <output directory>
 | -r | optional | Read input directory recursively. |
 | -pretty | optional | Enable pretty printing to SQF. |
 | --help | optional | Show usage. |
-| <input directory> | required | Directory to read ASL files from. |
-| <output directory> | required | Directory for SQF output. Can be the same as input directory. |
+| input directory | required | Directory to read ASL files from. |
+| output directory | required | Directory for SQF output. Can be the same as input directory. |
 
 **Example:**
 
diff --git a/ToDo.md b/ToDo.md
index 4eb2482..bd1bb5d 100644
--- a/ToDo.md
+++ b/ToDo.md
@@ -11,6 +11,9 @@
 * ~~negative values e.g. -1, operator !~~
 * ~~tokenizer splits commands like "format" -> for, mat~~
 * ~~try ... catch~~
+* better error reporting
+    - recover panic
+    - line, column
 
 ## Special cases
 
diff --git a/in/sub/empty.asl b/in/sub/empty.asl
new file mode 100644
index 0000000..e69de29
diff --git a/out/sub/empty.sqf b/out/sub/empty.sqf
new file mode 100644
index 0000000..e69de29
diff --git a/src/asl/parser.go b/src/asl/parser.go
index d1d320d..a95246b 100644
--- a/src/asl/parser.go
+++ b/src/asl/parser.go
@@ -9,7 +9,9 @@ const TAB = "    "
 // Parses tokens, validates code to a specific degree
 // and writes SQF code into desired location.
 func Parse(token []Token, prettyPrinting bool) string {
-	initParser(token, prettyPrinting)
+	if !initParser(token, prettyPrinting) {
+	    return ""
+	}
 
 	for tokenIndex < len(token) {
 		parseBlock()
diff --git a/src/asl/parserHelper.go b/src/asl/parserHelper.go
index f1b31b2..d8cd090 100644
--- a/src/asl/parserHelper.go
+++ b/src/asl/parserHelper.go
@@ -7,9 +7,9 @@ var offset int
 var pretty bool
 
 // Initilizes the parser.
-func initParser(token []Token, prettyPrinting bool) {
+func initParser(token []Token, prettyPrinting bool) bool {
 	if len(token) == 0 {
-		panic("No tokens provided")
+		return false
 	}
 
 	tokens = token
@@ -17,6 +17,8 @@ func initParser(token []Token, prettyPrinting bool) {
 	out = ""
 	offset = 0
 	pretty = prettyPrinting
+	
+	return true
 }
 
 // Returns true, if current token matches expected one.