lambda
Haskell asks computation to become visible. A function receives a value and returns a value; between those shorelines there is no hidden tide, no mutable weather, no concealed state.
“Elegance emerges when effects are named.”
Its discipline is not austerity. It is a spacious room where ideas can be observed without noise, composed without friction, and reasoned about as if they were lines of ink on handmade paper.
purity
foldMap :: Monoid m => (a -> m) -> t a -> m
traverse :: Applicative f => (a -> f b) -> t a -> f (t b)
compose :: (b -> c) -> (a -> b) -> a -> c
pure :: a -> f a
bind :: m a -> (a -> m b) -> m b
sequence :: [m a] -> m [a]
Hover a concept. The graph breathes toward it.
monadic
Algebraic data types give form to intention. They let a program become a house with visible beams: sum and product, choice and combination, absence and arrival.
Across decades, Haskell has remained a place where theory is allowed to mature into craft. Its abstractions are not ornament. They are joinery, precise and patient, holding the structure together without calling attention to their strength.
In that restraint, the language keeps offering a rare promise: code that can be read not only by a machine, but by the mind that must return to it years later.
Pure functions. Lazy evaluation. Elegant types.