Added environment with basic math functions

Signed-off-by: teo3300 <matteo.rogora@live.it>

src/envs.rs

@@ -1,6 +1,7 @@
 use std::collections::HashMap;
 
-use crate::types::{KeyType, MalRet, MalType};
+use crate::types::MalType::{Fun, Str};
+use crate::types::{int_op, MalArgs, MalRet, MalType};
 
 pub struct Env {
     map: HashMap<String, MalType>,
@@ -8,16 +9,29 @@ pub struct Env {
 
 impl Env {
     pub fn new() -> Self {
-        Env {
+        let mut env = Env {
             map: HashMap::new(),
+        };
+        env.init();
+        env
+    }
+
+    pub fn solve(&self, sym: String) -> MalRet {
+        match self.map.get(&sym) {
+            Some(val) => Ok(val.clone()),
+            None => Err(format!("symbol {:?} not defined", sym)),
         }
     }
 
-    pub fn solve(&self, sym: KeyType) -> MalRet {
-        let v = sym.val;
-        match self.map.get(&v) {
-            Some(val) => Ok(val.clone()),
-            None => Err(format!("symbol {:?} not defined", v)),
-        }
+    fn define(&mut self, sym: &str, f: fn(MalArgs) -> MalRet) {
+        self.map.insert(sym.to_string(), Fun(f));
+    }
+
+    fn init(&mut self) {
+        self.define("test", |_| Ok(Str("This is a test function".to_string())));
+        self.define("+", |args| int_op(0, |a, b| a + b, args));
+        self.define("-", |args| int_op(0, |a, b| a - b, args));
+        self.define("*", |args| int_op(1, |a, b| a * b, args));
+        self.define("/", |args| int_op(1, |a, b| a / b, args));
     }
 }

src/main.rs

@@ -40,8 +40,8 @@ fn main() {
                         println!("; [{}]> Error {}", num, err);
                     }
                 }
+                num += 1;
             }
-            num += 1;
             break;
         }
     }

src/mal_core.rs

@@ -1,17 +1,24 @@
 use crate::envs::Env;
 use crate::types::MalType::*;
-use crate::types::{MalRet, MalType};
+use crate::types::{MalArgs, MalRet, MalType};
 
-fn function_call(list: MalType) -> MalRet {
+fn call_func(func: &MalType, args: MalArgs) -> MalRet {
+    match func {
+        Fun(func) => func(args),
+        _ => panic!("Calling not a function"),
+    }
+}
+
+fn eval_func(list: MalType) -> MalRet {
     match list {
         List(list) => {
-            let _func = &list[0];
-            if list.len() > 1 {
-                let _ast = &list[1..list.len() - 1];
-                todo!("call: func(args)");
+            let func = &list[0];
+            let args = if list.len() > 1 {
+                &list[1..]
             } else {
-                todo!("call: func()");
-            }
+                &list[0..0]
+            };
+            call_func(func, args.to_vec())
         }
         _ => Err("YOU SHOULD NOT BE HERE".to_string()),
     }
@@ -21,10 +28,10 @@ pub fn eval(ast: MalType, env: &Env) -> MalRet {
     match &ast {
         List(list) => {
             if list.is_empty() {
-                Ok(ast)
+                Ok(Nil)
+                // Previously Ok(ast)
             } else {
-                let ev = eval_ast(ast, env)?;
-                function_call(ev)
+                eval_func(eval_ast(ast, env)?)
             }
         }
         _ => eval_ast(ast, env),
@@ -42,10 +49,10 @@ fn eval_list(list: Vec<MalType>, env: &Env) -> MalRet {
     Ok(List(ret))
 }
 
-pub fn eval_ast(ast: MalType, env: &Env) -> MalRet {
+fn eval_ast(ast: MalType, env: &Env) -> MalRet {
     match ast {
-        Sym(sym) => env.solve(sym), // resolve
+        Sym(sym) => env.solve(sym),
         List(list) => eval_list(list, env),
-        _ => Ok(ast), // Default behavior, do not resolve
+        _ => Ok(ast),
     }
 }

src/printer.rs

@@ -5,14 +5,15 @@ use crate::types::MalType::*;
 pub fn pr_str(ast: &MalType, print_readably: bool) -> String {
     match ast {
         Nil => "nil".to_string(),
-        Sym(sym) | Key(sym) => sym.val.to_string(),
+        Sym(sym) => sym.to_string(),
+        Key(sym) => sym[1..sym.len() - 1].to_string(),
         Int(val) => val.to_string(),
         Bool(val) => val.to_string(),
         Str(str) => {
             if print_readably {
-                escape_str(&str.val)
+                escape_str(str)
             } else {
-                str.val.to_string()
+                str.to_string()
             }
         }
         List(el) => format!(
@@ -33,9 +34,10 @@ pub fn pr_str(ast: &MalType, print_readably: bool) -> String {
         Map(el) => format!(
             "{{{}}}",
             el.iter()
-                .map(|sub| vec![sub.0.val.to_string(), pr_str(sub.1, print_readably)].join(" "))
+                .map(|sub| vec![sub.0.to_string(), pr_str(sub.1, print_readably)].join(" "))
                 .collect::<Vec<String>>()
                 .join(" ")
         ),
+        Fun(func) => format!("{:?}", func),
     }
 }

src/reader.rs

@@ -1,7 +1,6 @@
 // Specyfy components in "types"
 use crate::types::*;
 // By specifying enum variants it's possible to omit namespace
-use crate::types::KeyVar;
 use crate::types::MalType::*;
 
 use regex::Regex;
@@ -72,11 +71,11 @@ impl Reader {
                 if Regex::new(r"^-?[0-9]+$").unwrap().is_match(tk) {
                     Ok(Int(tk.parse::<isize>().unwrap()))
                 } else if tk.starts_with('\"') {
-                    Ok(Str(map_key(KeyVar::Str, &unescape_str(tk))))
+                    Ok(Str(unescape_str(tk)))
                 } else if tk.starts_with(':') {
-                    Ok(Key(map_key(KeyVar::Key, tk)))
+                    Ok(Key(format!("ʞ{}", tk)))
                 } else {
-                    Ok(Sym(map_key(KeyVar::Sym, tk)))
+                    Ok(Sym(tk.to_string()))
                 }
             }
         }

src/step2_eval.rs

@@ -36,6 +36,7 @@ fn PRINT(output: MalType) -> String {
 
 pub fn rep(input: &str, env: &Env) -> Result<String, String> {
     let ast = READ(input)?;
+    // println!("{:#?}", ast);
     let out = EVAL(ast, env)?;
     Ok(PRINT(out))
 }

src/types.rs

@@ -2,35 +2,16 @@
 
 use std::collections::HashMap;
 
-#[derive(Debug, Clone, Hash, Eq, PartialEq)]
-pub enum KeyVar {
-    Key,
-    Sym,
-    Str,
-}
-
-#[derive(Debug, Clone, Hash, Eq, PartialEq)]
-pub struct KeyType {
-    pub val: String,
-    var: KeyVar,
-}
-
-pub fn map_key(var: KeyVar, val: &str) -> KeyType {
-    KeyType {
-        val: val.to_string(),
-        var,
-    }
-}
-
 // All Mal types should inherit from this
 #[derive(Debug, Clone)]
 pub enum MalType {
     List(Vec<MalType>),
     Vector(Vec<MalType>),
-    Map(HashMap<KeyType, MalType>),
-    Sym(KeyType),
-    Key(KeyType),
-    Str(KeyType),
+    Map(HashMap<String, MalType>),
+    Fun(fn(MalArgs) -> MalRet),
+    Sym(String),
+    Key(String),
+    Str(String),
     Int(isize),
     Bool(bool),
     Nil,
@@ -87,3 +68,20 @@ pub fn unescape_str(s: &str) -> String {
         .replace("\\n", "\n")
         .replace("\\\"", "\"")
 }
+
+use MalType::Int;
+
+pub fn int_op(set: isize, f: fn(isize, isize) -> isize, args: MalArgs) -> MalRet {
+    let mut tmp: isize = set;
+    for el in args {
+        match el {
+            Int(val) => {
+                tmp = f(tmp, val);
+            }
+            _ => {
+                return Err(format!("{:?} is not a number", el));
+            }
+        }
+    }
+    Ok(Int(tmp))
+}