__str__ and instances as return values
20-minute lesson · module-classes-04
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__str__ and instances as return values
20-minute lesson · module-classes-04
- Define `__str__` so `print` and `str()` show a readable description.
- Explain why the default object representation is unhelpful.
- Write a method that returns a brand-new instance instead of mutating.
- Contrast a mutating method with one that returns a fresh object.
Source attribution
Status: adapted
How to Think Like a Computer Scientist: Interactive Edition — source · Classes and Objects - the Basics / The __str__ Method / Instances as Return Values
Adaptation notes. Reading rewritten in our voice. A Point class gets a __str__ and a `shifted` method that returns a new Point. Hidden tests check the string form and that returning-a-new-instance leaves the original unchanged.
License notes. Original chapter is GNU FDL 1.3 (Brad Miller and David Ranum). No verbatim text from the original is reproduced here.