Add Symbol struct to represent symbols

src/ast.rs

@@ -1,8 +1,8 @@
-use crate::types::{Expression, List, Number};
+use crate::types::{Expression, List, Number, Symbol};
 
 #[derive(Debug, Eq, PartialEq, Clone)]
 pub enum Expr {
-    Symbol(String),
+    Sym(Symbol),
     Str(String),
     Num(Number),
     Comment,
@@ -18,7 +18,7 @@ impl Expr {
     }
 
     pub fn make_symbol(v: String) -> Expr {
-        Expr::Symbol(v)
+        Expr::Sym(Symbol::new(v))
     }
 
     pub fn make_string(v: String) -> Expr {

src/compiler.rs

@@ -3,7 +3,7 @@ use inkwell::context::Context;
 use inkwell::module::Module;
 use inkwell::values::{BasicValue, BasicValueEnum, FloatValue, FunctionValue, PointerValue};
 
-use crate::expr::Expression;
+use crate::types::Expression;
 use std::collections::HashMap;
 
 pub struct Compiler<'a, 'ctx> {

src/reader.rs

@@ -1,4 +1,5 @@
-use crate::ast::{Expr, Number};
+use crate::ast::Expr;
+use crate::types::Number;
 use std::io::{BufReader, Read};
 
 pub type ReadResult = Result<Expr, String>;
@@ -249,6 +250,9 @@ impl ExprReader {
                 None => break,
             }
         }
+
+        // TODO: Move this to ast module and use the `new` function on
+        // Number struct
         if is_double {
             Ok(Expr::make_number(Number::Float(
                 string.parse::<f64>().unwrap(),

src/types.rs

@@ -1,7 +1,9 @@
 pub mod core;
 pub mod list;
 pub mod number;
+pub mod symbol;
 
 pub use self::core::Expression;
 pub use self::list::List;
 pub use self::number::Number;
+pub use self::symbol::Symbol;

src/types/number.rs

@@ -14,6 +14,7 @@ pub enum Number {
 
 impl PartialEq for Number {
     fn eq(&self, other: &Self) -> bool {
+        // TODO: Eval other
         let comb = (&self, &other);
 
         match comb {

src/types/symbol.rs

@@ -0,0 +1,25 @@
+use crate::types::Expression;
+
+#[derive(Debug, Clone)]
+pub struct Symbol {
+    name: String,
+}
+
+impl PartialEq for Symbol {
+    fn eq(&self, other: &Self) -> bool {
+        self.name == other.name
+    }
+}
+
+impl Eq for Symbol {}
+
+impl Expression for Symbol {
+    fn eval() {}
+    fn code_gen() {}
+}
+
+impl Symbol {
+    pub fn new(name: String) -> Self {
+        Symbol { name }
+    }
+}