Update examples

Author: johnsamuelwrites

getting-started/repl.md

@@ -219,8 +219,8 @@ Expected output: `6`
 
 ```python
 let x = 2
-let y = 3
-print(x + y)
+let z = 3
+print(x + z)
 
 let total = 0
 for idx in range(4):

language-guide/functions-classes.md

@@ -186,6 +186,8 @@ def print_banner(text):
     print(text.center(40))
     print("=" * 40)
     # implicit return None
+
+print_banner("Hello")
 ```
 
 ---
@@ -477,9 +479,9 @@ print(temp.fahrenheit)   # 32.0
 
 ```python
 class Vector:
-    def __init__(self, x, y):
+    def __init__(self, x, y_val):
         self.x = x
-        self.y = y
+        self.y = y_val
 
     def __add__(self, other):
         return Vector(self.x + other.x, self.y + other.y)

language-guide/syntax.md

@@ -356,6 +356,8 @@ def f(
 def greet(name, greeting="Hello", times=1):
     for _ in range(times):
         print(f"{greeting}, {name}")
+
+greet("World")
 ```
 
 ### Type Annotations

reference/numerals.md

@@ -201,7 +201,9 @@ Multilingual programs can use any supported numeral literal directly:
 # English program with Devanagari numeral
 let count = ४२        # equivalent to 42
 print(count + 8)     # 50
+```
 
+```python
 # French program with Arabic-Indic numeral
 soit total = ٣٠ + ١٢
 afficher(total)      # 42