implement hideously inefficient fix to work around rust

Signed-off-by: Ava Hahn <ava@aidanis.online>

src/sym.rs

@@ -68,7 +68,7 @@ pub struct Symbol {
 
 impl SymTable {
     pub fn new() -> SymTable {
-        SymTable{0: HashMap::<String, Symbol>::new()}
+        SymTable(HashMap::<String, Symbol>::new())
     }
 
     pub fn get(&self, arg: &String) -> Option<&Symbol> {
@@ -84,7 +84,7 @@ impl SymTable {
     }
 
     pub fn call_symbol(&mut self, name: &String, args: &Seg, call_func: bool) -> Result<Box<Ctr>, String> {
-        let symbol = match self.get(name) {
+        let symbol = match self.remove(name) {
             Some(s) => s,
             None => return Err(format!("undefined symbol: {}", name)),
         };
@@ -100,7 +100,16 @@ impl SymTable {
             cond_args = &outer_scope_seg_holder;
         }
 
-        symbol.call(cond_args, self)
+        let res = symbol.call(cond_args, self);
+        self.insert(name.to_string(), symbol);
+
+        res
+    }
+}
+
+impl Default for SymTable {
+    fn default() -> Self {
+        Self::new()
     }
 }
 
@@ -194,6 +203,7 @@ impl Symbol {
         let outer_scope_eval: Box<Ctr>;
         if self.conditional_branches {
             let outer_scope_eval_result = eval(args, syms);
+            // dont listen to clippy. using ? will move the value.
             if let Err(s) = outer_scope_eval_result {
                 return Err(s);
             }