ch14

ch14/samples/typing.examples.py

@@ -0,0 +1,77 @@
+# samples/typing.examples.py
+
+
+###############################################
+# This module is not supposed to be executed! #
+###############################################
+
+
+# not strongly typed language
+a = 7
+b = "7"
+
+a + b == 14
+concatenate(a, b) == "77"
+
+
+# dynamic typing
+a = 7
+a * 2 == 14
+a = "Hello"
+a * 2 == "HelloHello"
+
+
+# other languages
+String greeting = "Hello";
+int m = 7;
+float pi = 3.141592;
+
+
+# function annotations
+def greet(first_name, last_name, age):
+    return f"Greeting {first_name} {last_name} of age {age}"
+
+def greet(
+    first_name: "First name of the person we are greeting",
+    last_name: "Last name of the person we are greeting",
+    age: "The person's age"
+) -> "Returns the greeting sentence":
+    return f"Greeting {first_name} {last_name} of age {age}"
+
+def greet(first_name: str, last_name: str, age: int = 18) -> str:
+    return f"Greeting {first_name} {last_name} of age {age}"
+
+
+# list
+from typing import List
+
+def process_words(words: List[str]):
+    for word in words:
+        # do something with word
+
+
+# dict
+from typing import Dict
+
+def process_users(users: Dict[str, int]):
+    for name, age in users.items():
+        # do something with name and age
+
+
+# optional
+from typing import Optional
+
+def greet_again(name: Optional[str] = None):
+    if name is not None:
+        print(f"Hello {name}!")
+    else:
+        print("Hey dude")
+
+
+# custom
+class Cat:
+    def __init__(self, name: str):
+        self.name = name
+
+def call_cat(cat: Cat):
+    return f"{cat.name}! Come here!"