Implemented numeric constants

src/build/Function.go

@@ -16,6 +16,7 @@ type Function struct {
 	Name      string
 	Head      token.List
 	Body      token.List
+	Variables map[string]*Variable
 	Assembler asm.Assembler
 }
 
@@ -36,6 +37,16 @@ func (f *Function) Compile() {
 
 		if line[0].Kind == token.Keyword {
 			switch line[0].Text() {
+			case "let":
+				name := line[1].Text()
+				value := line[3:]
+				fmt.Println("[variable]", name, value)
+
+				f.Variables[name] = &Variable{
+					Value:   line[3:],
+					IsConst: true,
+				}
+
 			case "return":
 				f.Assembler.Return()
 			}
@@ -61,16 +72,33 @@ func (f *Function) Compile() {
 			}
 
 			for i, list := range parameters {
-				if list[0].Kind == token.Number {
-					numAsText := list[0].Text()
-					n, _ := strconv.Atoi(numAsText)
+				switch list[0].Kind {
+				case token.Identifier:
+					name := list[0].Text()
+					variable := f.Variables[name]
+
+					if !variable.IsConst {
+						panic("Not implemented yet")
+					}
+
+					n, _ := strconv.Atoi(variable.Value[0].Text())
 					f.Assembler.MoveRegisterNumber(x64.SyscallArgs[i], uint64(n))
+
+				case token.Number:
+					value := list[0].Text()
+					n, _ := strconv.Atoi(value)
+					f.Assembler.MoveRegisterNumber(x64.SyscallArgs[i], uint64(n))
+
+				default:
+					panic("Unknown expression")
 				}
 			}
 
 			f.Assembler.Syscall()
 		}
 	}
+
+	f.Assembler.Return()
 }
 
 // Lines returns the lines in the function body.