feat(runner): add REPL welcome message and language version

src/consts.py

@@ -1,2 +1,3 @@
 MAX_FUNCTION_ARGS = 255
 CONSTRUCTOR_NAME = "init"
+VERSION = (0, 1, 0)

src/pebble.py

@@ -2,6 +2,7 @@ import sys
 from pathlib import Path
 from typing import Optional
 
+from src.consts import VERSION
 from src.interpreter.error import PebbleRuntimeError
 from src.position import Position
 from src.token import Token, TokenType
@@ -11,6 +12,11 @@ class Pebble:
     had_error: bool = False
     had_runtime_error: bool = False
 
+    @staticmethod
+    def version() -> str:
+        major, minor, patch = VERSION
+        return f"{major}.{minor}.{patch}"
+
     @staticmethod
     def run_file(path: str | Path):
         source: str = ""

src/runner.py

@@ -59,6 +59,9 @@ class Runner:
         interpreter: Interpreter = Interpreter()
         resolver: Resolver
 
+        print(f"Welcome to Pebble v{Pebble.version()}!")
+        print("Press CTRL+D to quit")
+
         brace_depth: int
         paren_depth: int
         buf: str = ""
@@ -110,7 +113,11 @@ class Runner:
             if Pebble.had_error:
                 Pebble.had_error = False
                 continue
+
+            try:
                 interpreter.interpret(program)
+            except KeyboardInterrupt:
+                print()
 
             if Pebble.had_runtime_error:
                 Pebble.had_runtime_error = False