parametric polymorphism does: a function works for any type T without knowing what T is

Functions can work with any data type without knowing it!

Imagine writing a recipe that can be used for any dish, not just one specific meal.

Parametric polymorphism lets you write a recipe (function) that can adapt to any dish (type T) without changing the recipe itself.

Example

You write a "bake" function that can bake a cake, a pie, or a loaf of bread, just by changing the ingredients (type T).

Remember this

It's like having a universal recipe that fits any dish!

Text adapted from Wikipedia, licensed under CC BY-SA 4.0.

Related concepts

the Y combinator does: enables recursion in languages without named functions

Can a computer program call itself to solve problems?

Dependent type

Dependent types depend on values, not just types

Lambda calculus

Lambda calculus represents data using only functions

Fundamental theorem of algebra

Did you know every polynomial has a secret root?

Curry–Howard correspondence

Proofs are programs, types are propositions

Kullback–Leibler divergence

KL divergence is not symmetric: D_KL(P||Q) ≠ D_KL(Q||P)

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