Glossary · Phase 7 · Software engineering
Type checker
A tool like mypy that reads type hints and reports mismatches, such as a string passed where a number is expected, without running the code.
Try it now
Choose the most precise type that's still true. Precise types catch more mistakes, but a type that lies is worse than none.
Learn it properly
Typing in depth · Generics, protocols, TypedDict, Literal and narrowing, checked by mypy. About 45 minutes.
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