Add new ReplAction type

schala-repl/src/repl/command_tree.rs

@@ -3,7 +3,9 @@ use super::Repl;
 pub type BoxedCommandFunction = Box<(fn(&mut Repl, &[&str]) -> Option<String>)>;
 
 /// A CommandTree is either a `Terminal` or a `NonTerminal`. When command parsing reaches the first
-/// Terminal, it will execute the `BoxedCommandFunction` found there with any remaining arguments
+/// Terminal, it will use the `ReplAction` found there to find an appropriate function to execute,
+/// and then execute it with any remaining arguments
+//TODO remove function: BoxedCommandFunction
 #[derive(Clone)]
 pub enum CommandTree {
   Terminal {
@@ -11,22 +13,32 @@ pub enum CommandTree {
     children: Vec<CommandTree>,
     help_msg: Option<String>,
     function: BoxedCommandFunction,
+    action: ReplAction,
   },
   NonTerminal {
     name: String,
     children: Vec<CommandTree>,
     help_msg: Option<String>,
+    action: ReplAction,
   },
+  //TODO get rid of Top
   Top(Vec<CommandTree>),
 }
 
+#[derive(Debug, Clone)]
+pub enum ReplAction {
+  Null,
+  Help,
+  QuitProgram
+}
+
 impl CommandTree {
   pub fn nonterm_no_further_tab_completions(s: &str, help: Option<&str>) -> CommandTree {
-    CommandTree::NonTerminal {name: s.to_string(), help_msg: help.map(|x| x.to_string()), children: vec![] }
+    CommandTree::NonTerminal {name: s.to_string(), help_msg: help.map(|x| x.to_string()), children: vec![], action: ReplAction::Null }
   }
 
   pub fn terminal(s: &str, help: Option<&str>, children: Vec<CommandTree>, function: BoxedCommandFunction) -> CommandTree {
-    CommandTree::Terminal {name: s.to_string(), help_msg: help.map(|x| x.to_string()), function, children }
+    CommandTree::Terminal {name: s.to_string(), help_msg: help.map(|x| x.to_string()), function, children, action: ReplAction::Null }
   }
 
   pub fn nonterm(s: &str, help: Option<&str>, children: Vec<CommandTree>) -> CommandTree {
@@ -34,6 +46,7 @@ impl CommandTree {
       name: s.to_string(),
       help_msg: help.map(|x| x.to_string()),
       children,
+      action: ReplAction::Null
     }
   }