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README.md

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 # clox
 
-Lox Interpreter in C++ (under development)
+Lox(well, not really) Interpreter in C++ (under development)
+
+## Background
+This is a learning project for [Crafting interpreters](https://craftinginterpreters.com/).
+
+I'm not actully implementing the authentic Lox. I adopted it according to my likes.
+
+Lox is a language that is very similar to C, but with dynamic types. Let's see an example.
+
+```
+// calculate the greatest common divisor
+function gcd(a, b) {
+  if (b == 0) return a;
+  while (a >= b) a = a - b;
+  return gcd(b, a);
+}
+
+print gcd(99, 121);
+assert gcd(99, 121) == 11;
+```
+
+## Roadmap
 
 - [x] basic lexer
 - [x] basic parser
+- [x] ``+,-,*,/,=,==,!=,<,>,<=,>=,(,)``
+- [ ] ``+=, -=, *=, /=``
+- [x] support ++, --. but no `----a` bullshit! theses ops return rvalue
 - [x] print statement
 - [x] expr statement
 - [x] var declartion
 - [x] block scoping
 - [x] for, while block
 - [x] branch
+- [x] assert statement
+- [x] **testing the language with itself (built-in assert)!** see `./tests`
 - [ ] no continue! i'm lazy
 - [x] break
 - [x] function