Implemented register to register instructions

src/build/Variable.go

@@ -1,9 +1,11 @@
 package build
 
-import "git.akyoto.dev/cli/q/src/build/expression"
+import (
+	"git.akyoto.dev/cli/q/src/build/cpu"
+)
 
 // Variable represents a variable in a function.
 type Variable struct {
-	Name  string
-	Value *expression.Expression
+	Name     string
+	Register cpu.Register
 }