From c3c4ca6f7dd01e08df15bd0cfbad5c66157ad2f1 Mon Sep 17 00:00:00 2001
From: Marvin Blum <marvin@marvinblum.de>
Date: Sun, 25 Oct 2015 13:51:53 +0100
Subject: [PATCH] Added try ... catch.

---
 ToDo.md                   |  2 +-
 in/simple.asl             |  9 ++++++---
 src/asl/parser.go         | 16 ++++++++++++++++
 src/asl/parser_test.go    |  7 +++++++
 src/asl/tokenizer.go      |  4 +++-
 src/main/asl.go           |  2 +-
 test/parser_try_catch.asl |  5 +++++
 7 files changed, 39 insertions(+), 6 deletions(-)
 create mode 100644 test/parser_try_catch.asl

diff --git a/ToDo.md b/ToDo.md
index 6a1df76..97a12fc 100644
--- a/ToDo.md
+++ b/ToDo.md
@@ -10,7 +10,7 @@
 * ~~inline buildin function call -> foo(a)(bar(x)(y));~~
 * ~~negative values e.g. -1, operator !~~
 * ~~tokenizer splits commands like "format" -> for, mat~~
-* try ... catch
+* ~~try ... catch~~
 
 ## Special cases
 
diff --git a/in/simple.asl b/in/simple.asl
index 0bc4a9c..f11ba71 100644
--- a/in/simple.asl
+++ b/in/simple.asl
@@ -1,3 +1,6 @@
-// TODO:
-//var _x = setHitIndex(vehicle()(player))(1, 1);
-
+try {
+    var x = 100;
+    doSomething(x);
+} catch {
+    errorHandling();
+}
diff --git a/src/asl/parser.go b/src/asl/parser.go
index 4d5bb0a..b85cc7b 100644
--- a/src/asl/parser.go
+++ b/src/asl/parser.go
@@ -35,6 +35,8 @@ func parseBlock() {
 		parseFunction()
 	} else if accept("return") {
 		parseReturn()
+	} else if accept("try") {
+	    parseTryCatch()
 	} else if accept("case") || accept("default") {
 		return
 	} else {
@@ -232,6 +234,20 @@ func parseReturn() {
 	appendOut(";", true)
 }
 
+func parseTryCatch() {
+    expect("try")
+    expect("{")
+    appendOut("try {", true)
+    parseBlock()
+    expect("}")
+    expect("catch")
+    expect("{")
+    appendOut("} catch {", true)
+    parseBlock()
+    expect("}")
+    appendOut("};", true)
+}
+
 // Everything that does not start with a keyword.
 func parseStatement() {
 	// empty block
diff --git a/src/asl/parser_test.go b/src/asl/parser_test.go
index 218cc35..80b3c76 100644
--- a/src/asl/parser_test.go
+++ b/src/asl/parser_test.go
@@ -101,6 +101,13 @@ func TestParserOperator(t *testing.T) {
 	equal(t, got, want)
 }
 
+func TestParserTryCatch(t *testing.T) {
+	got := getCompiled(t, "test/parser_try_catch.asl")
+	want := "try {\n} catch {\n};\n"
+
+	equal(t, got, want)
+}
+
 func getCompiled(t *testing.T, file string) string {
 	code, err := ioutil.ReadFile(file)
 
diff --git a/src/asl/tokenizer.go b/src/asl/tokenizer.go
index 047aeea..6d28c70 100644
--- a/src/asl/tokenizer.go
+++ b/src/asl/tokenizer.go
@@ -41,7 +41,9 @@ var keywords = []string{
 	"false",
 	"case",
 	"default",
-	"return"}
+	"return",
+	"try",
+	"catch"}
 
 var whitespace = []byte{' ', '\n', '\t'}
 var identifier = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789_"
diff --git a/src/main/asl.go b/src/main/asl.go
index 5393431..332f11c 100644
--- a/src/main/asl.go
+++ b/src/main/asl.go
@@ -19,7 +19,7 @@ func usage() {
 
 func main() {
 	// read test file
-	code, _ := ioutil.ReadFile("in/complex.asl")
+	code, _ := ioutil.ReadFile("in/simple.asl")
 	token := asl.Tokenize(code)
 	out := asl.Parse(token, true)
 
diff --git a/test/parser_try_catch.asl b/test/parser_try_catch.asl
new file mode 100644
index 0000000..ca777d4
--- /dev/null
+++ b/test/parser_try_catch.asl
@@ -0,0 +1,5 @@
+try {
+    // ...
+} catch {
+    // ...
+}