apparently you can derive default

dhconnelly · Nov 15, 2023 · 8538b66 · 8538b66
1 parent 5c568d2
commit 8538b66
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Showing 2 changed files with 18 additions and 28 deletions.
diff --git a/src/analyzer.rs b/src/analyzer.rs
@@ -45,7 +45,7 @@ struct Analyzer {
 
 impl Default for Analyzer {
     fn default() -> Analyzer {
-        let mut ctx = SymbolTable::new();
+        let mut ctx = SymbolTable::default();
         builtins::install(&mut ctx);
         Analyzer::with_context(ctx)
     }
@@ -248,7 +248,7 @@ mod test {
                 }),
             ],
         };
-        let mut ctx = SymbolTable::new();
+        let mut ctx = SymbolTable::default();
         ctx.def_global(
             "println",
             Type::Fn(FnType {
@@ -262,7 +262,7 @@ mod test {
 
     #[test]
     fn test_func() {
-        let mut ctx = SymbolTable::new();
+        let mut ctx = SymbolTable::default();
         ctx.def_global(
             "itoa",
             Type::Fn(FnType {
@@ -541,7 +541,7 @@ mod test {
 
     #[test]
     fn test_call() {
-        let mut ctx = SymbolTable::new();
+        let mut ctx = SymbolTable::default();
         ctx.push_frame();
         ctx.def_local(
             String::from("println"),
@@ -566,7 +566,7 @@ mod test {
 
     #[test]
     fn test_ident() {
-        let mut ctx = SymbolTable::new();
+        let mut ctx = SymbolTable::default();
         ctx.push_frame();
         ctx.def_local(String::from("foo"), Type::Int);
         ctx.def_local(String::from("bar"), Type::Str);
@@ -584,7 +584,7 @@ mod test {
     fn test_literal() {
         let inputs: &[&[u8]] = &[b"27", b"\"hello, world\""];
         let expected = vec![Ok(Type::Int), Ok(Type::Str)];
-        let actual = analyze_exprs(inputs, SymbolTable::new());
+        let actual = analyze_exprs(inputs, SymbolTable::default());
         assert_eq!(expected, actual);
     }
 }
diff --git a/src/symbol_table.rs b/src/symbol_table.rs
@@ -7,7 +7,7 @@ struct SymbolInfo {
     typ: Type,
 }
 
-#[derive(Debug, Clone)]
+#[derive(Debug, Default, Clone)]
 pub struct SymbolTable {
     // TODO: supporting forward references will require supporting empty values
     // in the globals table
@@ -16,16 +16,19 @@ pub struct SymbolTable {
 }
 
 impl SymbolTable {
-    pub fn new() -> Self {
-        Self { globals: HashMap::new(), frames: Vec::new() }
-    }
-
     pub fn def_global<S: Into<String>>(&mut self, name: S, typ: Type) {
         let idx = self.globals.len();
         let name = name.into();
         self.globals.insert(name, SymbolInfo { idx, typ });
     }
 
+    fn get_global(&self, name: &str) -> Option<Resolution> {
+        self.globals.get(name).map(|SymbolInfo { idx, typ }| Resolution {
+            reference: Reference::Global { idx: *idx },
+            typ: typ.clone(),
+        })
+    }
+
     pub fn push_frame(&mut self) {
         self.frames.push(HashMap::new());
     }
@@ -34,11 +37,10 @@ impl SymbolTable {
         self.frames.pop().unwrap();
     }
 
-    fn get_global(&self, name: &str) -> Option<Resolution> {
-        self.globals.get(name).map(|SymbolInfo { idx, typ }| Resolution {
-            reference: Reference::Global { idx: *idx },
-            typ: typ.clone(),
-        })
+    pub fn def_local<S: Into<String>>(&mut self, name: S, typ: Type) {
+        let frame = self.frames.last_mut().unwrap();
+        let idx = frame.len();
+        frame.insert(name.into(), SymbolInfo { idx, typ });
     }
 
     fn get_frame(&self, name: &str, depth: usize) -> Option<Resolution> {
@@ -54,16 +56,4 @@ impl SymbolTable {
             .find_map(|depth| self.get_frame(name, depth))
             .or_else(|| self.get_global(name))
     }
-
-    pub fn def_local<S: Into<String>>(&mut self, name: S, typ: Type) {
-        let frame = self.frames.last_mut().unwrap();
-        let idx = frame.len();
-        frame.insert(name.into(), SymbolInfo { idx, typ });
-    }
-}
-
-impl Default for SymbolTable {
-    fn default() -> Self {
-        Self::new()
-    }
 }