added stringfunctions.py

strings/stringfunctions.py

@@ -1,4 +1,4 @@
-def is_upper(string):
+def is_upper(string: str) -> bool:
     """
     Check if all characters in the string are uppercase letters.
     
@@ -10,7 +10,7 @@ def is_upper(string):
     """
     return all(ord(char) >= 65 and ord(char) <= 90 for char in string)
 
-def is_lower(string):
+def is_lower(string: str) -> bool:
     """
     Check if all characters in the string are lowercase letters.
     
@@ -22,7 +22,7 @@ def is_lower(string):
     """
     return all(ord(char) >= 97 and ord(char) <= 122 for char in string)
 
-def is_alpha(string):
+def is_alpha(string: str) -> bool:
     """
     Check if all characters in the string are alphabetical (letters).
     
@@ -34,7 +34,7 @@ def is_alpha(string):
     """
     return all(char.isalpha() for char in string)
 
-def is_alnum(string):
+def is_alnum(string: str) -> bool:
     """
     Check if all characters in the string are alphanumeric (letters or digits).
     
@@ -46,7 +46,7 @@ def is_alnum(string):
     """
     return all(char.isalnum() for char in string)
 
-def is_decimal(string):
+def is_decimal(string: str) -> bool:
     """
     Check if all characters in the string are decimal digits.
     
@@ -58,7 +58,7 @@ def is_decimal(string):
     """
     return all(char.isdigit() for char in string)
 
-def is_space(string):
+def is_space(string: str) -> bool:
     """
     Check if all characters in the string are whitespace characters.
     
@@ -70,7 +70,7 @@ def is_space(string):
     """
     return all(char.isspace() for char in string)
 
-def is_title(string):
+def is_title(string: str) -> bool:
     """
     Check if the string is in title case (first letter of each word is capital).
     
@@ -80,4 +80,22 @@ def is_title(string):
     Returns:
         bool: True if the string is in title case, False otherwise.
     """
-    return string.istitle()
+    return string.istitle()
+
+# Tests
+assert is_upper("HELLO")
+assert not is_upper("Hello")
+assert is_lower("hello")
+assert not is_lower("Hello")
+assert is_alpha("Hello")
+assert not is_alpha("Hello123")
+assert is_alnum("Hello123")
+assert not is_alnum("Hello 123")
+assert is_decimal("12345")
+assert not is_decimal("12.345")
+assert is_space("    \t\n")
+assert not is_space("Hello")
+assert is_title("This Is A Title Case String")
+assert not is_title("This is Not a Title Case String")
+
+print("All tests passed!")