1 files changed, 70 insertions, 0 deletions
diff --git a/main.py b/main.py
new file mode 100644
index 0000000..a86d293
--- /dev/null
+++ b/main.py
@@ -0,0 +1,70 @@
+import sys
+
+from consts import *
+from tokenizer import tokenize
+from parser import build_tree
+
+
+# RUNTIME
+
+unary_operators = {
+    "-": lambda a: -a,
+    "+": lambda a: a
+}
+
+operators = {
+    "+": lambda a, b: a + b,
+    "-": lambda a, b: a - b,
+    "*": lambda a, b: a * b,
+    "^": lambda a, b: a ** b,
+}
+
+runtime = {
+    "x": 10
+}
+
+
+def factorial(n):
+    if n <= 1:
+        return 1
+    return n * factorial(n - 1)
+
+
+runtime_functions = {
+    "factorial": factorial
+}
+
+# END OF RUNTIME
+
+
+def expr_eval(node):
+    if node.type == NUMBER:
+        return node.value
+    elif node.type == SYMBOL:
+        return runtime.get(node.value)
+    elif node.type == FUNCALL:
+        fun_name = node.value[0]
+        args = list(map(expr_eval, node.value[1]))
+        return runtime_functions.get(fun_name)(*args)
+    elif node.type == OPERATOR:
+        if node.subtype == UNARY:
+            return unary_operators.get(node.left.subtype)(expr_eval(node.right))
+        else:
+            return operators.get(node.subtype)(expr_eval(node.left), expr_eval(node.right))
+
+
+def main(*argv):
+    if len(argv) != 0:
+        data = argv[0]
+    else:
+        data = "2 + 3 * 4"
+        # data = "(3 + 3 * 2) * -4"
+        # data = "(2 + factorial(4, )) * 9"
+
+    tokens = tokenize(data)
+    node1 = build_tree(tokens)
+    print(expr_eval(node1))
+
+
+if __name__ == "__main__":
+    main(*sys.argv[1:])