stream-stream-transform.nix

Source: /nix/store/mls72plk3raskl1r5afh3cl9ik3rn969-source/nix/stream-transform.nix

Module Description

Stream transformation operations - mapping and filtering

Combinators

filter

Keeps only elements matching a predicate.

Lazily filters stream, skipping elements that don’t match. May need to evaluate multiple steps to find next match.

Type Signature

(V -> Bool) -> Stream<S, V> -> Stream<S, V>

Parameters

• pred: Predicate function
• stream: Source stream

Example

runFx (toList (filter (x: x > 2) (fromList [1 2 3 4])))
# => [3 4]

See Also

• takeWhile - Take until predicate fails
• map - Transform all elements

map

Transforms each element in a stream.

Applies a pure function to every value in the stream, preserving structure and laziness.

Type Signature

(V -> U) -> Stream<S, V> -> Stream<S, U>

Parameters

• f: Transformation function
• stream: Source stream

Example

runFx (toList (map (x: x * 2) (fromList [1 2 3])))
# => [2 4 6]

See Also

• filter - Select elements
• flatMap - Transform and flatten

Generated from /nix/store/mls72plk3raskl1r5afh3cl9ik3rn969-source/nix/stream-transform.nix