enable panic function

Makefile

@@ -134,6 +134,7 @@ test/example:
 	${CELL} -d -t riscv tests/examples/string.cell && ckb-debugger --bin string | grep "eq"
 	${CELL} -d -t riscv tests/examples/strings.cell && ckb-debugger --bin strings | grep "aa-bb"
 	${CELL} -d -t riscv tests/examples/make-slice.cell && ckb-debugger --bin make-slice | grep "0422"
+	${CELL} -d -t riscv tests/examples/panic.cell && ckb-debugger --bin panic | grep "runtime panic: hah"
 	${CELL} -d -t riscv tests/examples/func.cell && ckb-debugger --bin func | grep "999"
 	${CELL} -t riscv tests/examples/cell-data.cell && ckb-debugger --bin cell-data
 	${CELL} -t riscv tests/examples/inputs.cell && ckb-debugger --bin inputs

compiler/compiler/func.go

@@ -397,6 +397,10 @@ func (c *Compiler) compileCallNode(v *parser.CallNode) value.Value {
 			return c.appendFuncCall(v)
 		case "print":
 			return c.printFuncCall(v)
+		case "panic":
+			message, _ := v.Arguments[0].(*parser.ConstantNode)
+			c.panic(c.contextBlock, message.ValueStr)
+			return value.Value{}
 		}
 	}
 

compiler/lexer/keywords.go

@@ -21,4 +21,5 @@ var keywords = map[string]struct{}{
 	"interface": {},
 	"range":     {},
 	"make":		 {},
+	"panic":	 {},
 }

compiler/parser/parser.go

@@ -335,6 +335,24 @@ func (p *parser) parseOneWithOptions(withAheadParse, withArithAhead, withIdentif
 			return outerConditionNode
 		}
 
+		if current.Val == "panic" {
+			p.i++
+			lParent := p.lookAhead(0)
+			p.expect(lParent, lexer.Item{Type: lexer.OPERATOR, Val: "("})
+			p.i++
+			args := p.parseUntil(lexer.Item{Type: lexer.OPERATOR, Val: ")"})
+			if len(args) != 1 {
+				panic("wrong number of arguments for panic(message)")
+			}
+			if _, ok := args[0].(*ConstantNode); !ok {
+				panic("wrong type of argument for panic(message)")
+			}
+			return &CallNode{
+				Function:  &NameNode{Name: "panic"},
+				Arguments: args,
+			}
+		}
+
 		// "make" is a construtor command for composed types
 		if current.Val == "make" {
 			p.i++

tests/examples/panic.cell

@@ -0,0 +1,6 @@
+package main
+
+func main() {
+	panic("hah")
+	return 0
+}