Add variable-to-variable assignment

demo/demo.rpy

@@ -6,7 +6,9 @@ if True:
     "Bob will be here in [x] seconds."
     if True:
         x = "1"
-        let x = "4"
+        let y = "4"
+        y = "5"
+        x = y
         "[x]"
     "Bob will be here in [x] seconds."
 "Bob will be here in [x] seconds."

renrs/src/parser/block.rs

@@ -37,12 +37,20 @@ impl CommandContext {
                     assign_type,
                     variable,
                     value,
-                } => match assign_type {
+                } => {
+                    let value = if let Token::Keyword(keyword) = value {
+                        self.context
+                            .borrow()
+                            .get_variables()
+                            .get(keyword)
+                            .unwrap_or_else(|| panic!("undefined variable `{keyword}`"))
+                            .clone()
+                    } else {
+                        value.clone()
+                    };
+                    match assign_type {
                         Define => panic!("define command should not be executed at runtime!"),
                         GlobalAssign => {
-                        if let Token::Keyword(_) = value {
-                            todo!("assignment variable interpolation isn't implemented");
-                        }
                             let root = self.context.borrow().get_root(&self.context);
                             // Don't want to re-borrow if root is self
                             let root = if Rc::ptr_eq(&self.context, &root) {
@@ -58,9 +66,6 @@ impl CommandContext {
                             return None;
                         }
                         Let => {
-                        if let Token::Keyword(_) = value {
-                            todo!("assignment variable interpolation isn't implemented");
-                        }
                             self.context
                                 .borrow()
                                 .variables
@@ -69,9 +74,6 @@ impl CommandContext {
                             return None;
                         }
                         Assign => {
-                        if let Token::Keyword(_) = value {
-                            todo!("assignment variable interpolation isn't implemented");
-                        }
                             let mut block_option = Some(self.context.clone());
                             let mut modified = false;
                             while let Some(block) = block_option {
@@ -94,6 +96,7 @@ impl CommandContext {
                             }
                             return None;
                         }
+                    }
                 },
                 Eat { .. } => return None,
             }