Python repr() Function

The repr() function returns a string representation of an object that can often be used to recreate the object. It's useful for debugging and logging because it gives more detail than just printing the value.

Syntax

repr(object)

Parameters:

• object – Any Python object you want to inspect.

Returns:

• A string that is a printable, and often evaluable, representation of the object.

Example 1: Using repr() with Strings

text = "Hello
World"
print(text)          # Output as interpreted by print
print(repr(text))    # Raw string representation

Hello
World
'Hello\nWorld'

Explanation: repr() shows the escape characters like \n instead of turning them into a newline. This helps you see the actual string content.

Example 2: Using repr() with Numbers

num = 3.14159
print(repr(num))

3.14159

With numbers, repr() behaves the same as str(), but it's more accurate for floating point values.

Example 3: Custom Objects and __repr__()

class Person:
    def __init__(self, name):
        self.name = name

    def __repr__(self):
        return f"Person(name='{self.name}')"

p = Person("Alice")
print(p)
print(repr(p))

Person(name='Alice')
Person(name='Alice')

Explanation: You can define your own __repr__() method to control how objects are displayed with repr().

Use Case: Debugging

When you're logging or printing complex data structures, repr() helps you see the full raw format, which is better for developers to inspect values and structure.

repr() vs str()

Function	Purpose
str()	Returns a readable version (for end users).
repr()	Returns an official, raw representation (for developers).

Common Mistakes

• Using repr() for display when str() is more readable for users.
• Forgetting to define __repr__() in custom classes — making debugging harder.

Interview Tip

If asked how to get the “developer version” of an object’s string, say repr(). It’s also used internally by the interpreter when displaying objects in the shell.

Summary

• repr() gives a detailed, unambiguous string representation of objects.
• Ideal for debugging, logging, and understanding what's really inside an object.
• You can customize its behavior in classes using __repr__().

Practice Problem

Create a class Book with attributes title and author. Override __repr__() to return something like: Book(title='...', author='...').

class Book:
    def __init__(self, title, author):
        self.title = title
        self.author = author

    def __repr__(self):
        return f"Book(title='{self.title}', author='{self.author}')"

b = Book("1984", "George Orwell")
print(repr(b))