In thi post, I plan to compare the ways TypeScript and Python do Type Narrowing. Let’s start with the definition of Type Narrowing:

Type Narrowing is a mechanism used to deduce and narrow down the type of a variable, expression, or set of values based on certain conditions or operations. It allows the type checker to infer a more specific type rather than one that is more general at the beginning. The inference is often achieved by analyzing the control flow, branches, or conditional statements within the code.

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