gitter-badger/lens-1

Cute lens syntax on top of Monocle: object.lens(_.a.b).set(v1).lens(_.c).modify(_ + v2)

lens

User-friendly lens syntax for mortals. Update values inside of nested case class instances without .copy .

(Based on Monocle)

SBT Dependency

"ai.x" %% "lens" % "1.0.0"

Usage

case class C( d: Int )
case class B( c: C )
case class A( b: B )
val a = A(B(C(3)))

Easy updates using .lens

a.lens(_.b.c.d).set( 5 )
a.lens(_.b.c.d).modify( _ + 2 )

Verbose update using .copy

a.copy(
  b = a.b.copy(
    c = a.b.c.copy(
      d = 5
)))
a.copy(
  b = a.b.copy(
    c = a.b.c.copy(
      d = a.b.c.d + 2
)))