Futu
Futumorphism citizen — a multi-layer unfold (BuildScheme) with X = Coattr[F, A], the free monad μX. A + F[X]. The build-side mirror of Histo. coalg: A => F[Coattr[F, A]] answers each slot with Coattr.Pure (keep unfolding) or Coattr.Roll (a prebuilt layer, no coalgebra call), so one step may emit several layers; the root seed enters as Coattr.Pure. An all-Pure coalgebra degenerates to Ana. Carries coalg so cross can fuse with Histo (→ Chrono) or Cata (→ Codyna). Stack-safe.
Attributes
- Source
- Futu.scala
- Graph
-
- Supertypes
-
class Objecttrait Matchableclass Any
Members list
Grouped members
Operations
Build-then-observe across the build-output ⇄ read-input seam, preserving structure, on a shared carrier F. Flip self (it must be reversible — Accessor[F] and ReverseAccessor[F], i.e. an Iso or Review over Direct) so it reads T from B, then andThen that under the same carrier. The result is the full Optic[B, A, C, D, F], not a collapsed getter: its read capability follows the carrier (.get for Direct), and self's read focus A survives as the composite's write-back focus.
Build-then-observe across the build-output ⇄ read-input seam, preserving structure, on a shared carrier F. Flip self (it must be reversible — Accessor[F] and ReverseAccessor[F], i.e. an Iso or Review over Direct) so it reads T from B, then andThen that under the same carrier. The result is the full Optic[B, A, C, D, F], not a collapsed getter: its read capability follows the carrier (.get for Direct), and self's read focus A survives as the composite's write-back focus.
This is exactly self.reverse.andThen(that). The motivating case is ana.cross(cata): a Review (the unfold) crossed with a getter on the built S (the fold) — a (materializing) hylomorphism whose .get reads the folded value. When that sits on a different carrier (a Prism, a Fold, …), the cross-carrier cross overload below is selected instead.
Seam: that's source is self's T and its back-type is self's S.
Attributes
- Inherited from:
- Optic
- Source
- Optic.scala
Type members
Types
Existential leftover carried alongside the focus — the type-level witness the carrier uses to rebuild T. Concrete at construction (Lens.apply sets X = S, Prism.apply sets X = S, …) and abstract when the optic is bound to Optic[…, F] without refinement.
Existential leftover carried alongside the focus — the type-level witness the carrier uses to rebuild T. Concrete at construction (Lens.apply sets X = S, Prism.apply sets X = S, …) and abstract when the optic is bound to Optic[…, F] without refinement.
Attributes
- Source
- Futu.scala
Value members
Concrete methods
The fused chrono seam: futu ∘ Histo — Hylo at the universal indices. The build threads the free monad (Coattr), the fold the cofree comonad (Attr); fused, no intermediate S.
The fused chrono seam: futu ∘ Histo — Hylo at the universal indices. The build threads the free monad (Coattr), the fold the cofree comonad (Attr); fused, no intermediate S.
Attributes
- Source
- Futu.scala
The fused mirror-of-dyna seam: futu ∘ node-blind Cata (→ Codyna) — opposite diagonal of the refold quadrant. Fuses; the Coattr free layers are threaded internally, no intermediate S.
The fused mirror-of-dyna seam: futu ∘ node-blind Cata (→ Codyna) — opposite diagonal of the refold quadrant. Fuses; the Coattr free layers are threaded internally, no intermediate S.
Attributes
- Source
- Futu.scala
Inherited methods
ANY outer ∘ read-only inner — the inner is honestly one-way (T = Unit: a Getter, AffineFold, or Fold), so only the two READ sides matter and the composite collapses to the read-only join of their strengths via compose.ReadCompose (Getter / PickFold / ForgetFold).
ANY outer ∘ read-only inner — the inner is honestly one-way (T = Unit: a Getter, AffineFold, or Fold), so only the two READ sides matter and the composite collapses to the read-only join of their strengths via compose.ReadCompose (Getter / PickFold / ForgetFold).
A trait member (not an extension in the companion) deliberately: once a receiver is statically one of the fused concrete classes, its andThen member overloads enter resolution and Scala 3 never falls back to extension methods when they all fail — the collapse must be in the member overload set to be reachable without an expected-type ascription.
Only the inner's T is pinned to Unit; its B stays free (IB) even though read-only inners always have B = Unit. That keeps this overload strictly LESS specific than the same-carrier andThen above (which accepts every argument this one does whenever B = Unit at the receiver), so a same-carrier read-only ∘ read-only call resolves unambiguously to the AssociativeFunctor path and this one fires exactly on the cross-seam cells the generic member cannot type.
Attributes
- Inherited from:
- Optic
- Source
- Optic.scala
Compose with another optic under the shared carrier F. Requires AssociativeFunctor[F]. Cross-carrier composition (Lens → Optional, Lens → Traversal, …) goes through the Morph-summoning overload of this same method.
Compose with another optic under the shared carrier F. Requires AssociativeFunctor[F]. Cross-carrier composition (Lens → Optional, Lens → Traversal, …) goes through the Morph-summoning overload of this same method.
Attributes
- Example
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case class Address(street: String) case class Person(address: Address) val streetLens = lens[Person](_.address).andThen(lens[Address](_.street)) - Inherited from:
- Optic
- Source
- Optic.scala
Close the carrier: given a modified focus B (and the leftover X already inside the F), reassemble the result T.
Close the carrier: given a modified focus B (and the leftover X already inside the F), reassemble the result T.
Attributes
- Inherited from:
- BuildScheme
- Source
- SchemeShapes.scala
Push the source S into the carrier, extracting the focus A and packing the leftover X. Paired with from to reconstruct T.
Push the source S into the carrier, extracting the focus A and packing the leftover X. Paired with from to reconstruct T.
Attributes
- Inherited from:
- BuildScheme
- Source
- SchemeShapes.scala