cats-eo-api-docs/dev.constructive.eo/CanFold

CanFold

dev.constructive.eo.CanFold

See theCanFold companion object

trait CanFold[S, A]

Capability: the foci A visible in an S can be folded through a Monoid — the carrier-free surface of any optic whose carrier admits forgetful.ForgetfulFold (every readable family; the primary surface of Fold and Traversal).

foldMap is the kernel; headOption / length / exists / foci ride on it. foci is the carrier-free counterpart of the raw-optic all extension (which returns foci still inside their carrier, List[F[X, A]]). Prefer this trait in consuming signatures; see CanGet for the doctrine and the coherence rule.

Attributes

Companion: object
Source: CanFold.scala
Graph
Supertypes: class Object

trait Matchable

class Any
Known subtypes: class BijectionIso[S, T, A, B]

class ForgetFold[S, F, A]

class GetReplaceLens[S, T, A, B]

class Getter[S, A]

class MendTearPrism[S, T, A, B]

class Optional[S, T, A, B]

class PickFold[S, A]

class PickMendPrism[S, A, B]

class SplitCombineLens[S, T, A, B, XA]

class SimpleLens[S, A, XA]
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