From 7e25d2e7a9e59bb64f1d9f41a8a521aed42c95c2 Mon Sep 17 00:00:00 2001 From: djspiewak Date: Sat, 3 Feb 2024 21:01:05 +0000 Subject: [PATCH] deploy: f58181da31dd5818751f0d17ef10b79b3ba847da --- datatypes/contt.html | 12 ++++++------ datatypes/eval.html | 4 ++-- datatypes/freeapplicative.html | 2 +- datatypes/freemonad.html | 4 ++-- datatypes/state.html | 4 ++-- typeclasses/bifoldable.html | 4 ++-- typeclasses/bifunctor.html | 2 +- typeclasses/bimonad.html | 2 +- typeclasses/contravariant.html | 16 ++++++++-------- typeclasses/eq.html | 2 +- typeclasses/foldable.html | 2 +- typeclasses/semigroup.html | 12 ++++++------ typeclasses/show.html | 6 +++--- 13 files changed, 36 insertions(+), 36 deletions(-) diff --git a/datatypes/contt.html b/datatypes/contt.html index 998db5137a..948b3102ae 100644 --- a/datatypes/contt.html +++ b/datatypes/contt.html @@ -286,7 +286,7 @@

ContT

Succeeded(user.id) } } -// eval: Eval[UserUpdateResult] = cats.Later@6dc7d6f7 +// eval: Eval[UserUpdateResult] = cats.Later@49eb5a6f

Finally we can run the resulting Eval to actually execute the computation:

eval.value
 // Persisting updated user to the DB: User(100,Bob,150)
@@ -308,7 +308,7 @@ 
// anotherComputation: ContT[Eval, UserUpdateResult, Map[String, String]] = FromFn(
 //   runAndThen = Single(
-//     f = cats.data.ContT$$Lambda$11671/0x00007f929dfb2940@7b2b2452,
+//     f = cats.data.ContT$$Lambda$14106/0x00007f75336430e8@ed6c40c,
 //     index = 0
 //   )
 // )
@@ -319,7 +319,7 @@ 
Succeeded(userFields("id").toInt)
   }
 }
-// anotherEval: Eval[UserUpdateResult] = cats.Eval$$anon$5@30918467
+// anotherEval: Eval[UserUpdateResult] = cats.Eval$$anon$5@45cf4088
 
 anotherEval.value
 // Persisting these fields to the DB: Map(id -> 100, name -> Bob, age -> 150)
@@ -336,7 +336,7 @@ 
// updateUserModel: ContT[Eval, UserUpdateResult, User] = FromFn(
 //   runAndThen = Single(
-//     f = cats.data.ContT$$Lambda$11671/0x00007f929dfb2940@e2d2316,
+//     f = cats.data.ContT$$Lambda$14106/0x00007f75336430e8@42ff6de6,
 //     index = 0
 //   )
 // )
@@ -370,7 +370,7 @@ 
updateUserModel flatMap persistToDb flatMap publishEvent
 // chainOfContinuations: ContT[Eval, UserUpdateResult, UserUpdateResult] = FromFn(
 //   runAndThen = Single(
-//     f = cats.data.ContT$$Lambda$11675/0x00007f929dfb32c8@369bdc92,
+//     f = cats.data.ContT$$Lambda$14110/0x00007f7533643a70@1b8fa113,
 //     index = 0
 //   )
 // )
@@ -381,7 +381,7 @@ 
finalResult
   }
 }
-// eval: Eval[UserUpdateResult] = cats.Eval$$anon$5@1a5914c3
+// eval: Eval[UserUpdateResult] = cats.Eval$$anon$5@78f8c22c
 
 eval.value
 // Updated user model
diff --git a/datatypes/eval.html b/datatypes/eval.html
index 233d1757bf..90dff492ce 100644
--- a/datatypes/eval.html
+++ b/datatypes/eval.html
@@ -257,7 +257,7 @@ 
println("Running expensive calculation...")
   1 + 2 * 3
 }
-// lazyEval: Eval[Int] = cats.Later@1d852f39
+// lazyEval: Eval[Int] = cats.Later@5f3ddfe4
 
 lazyEval.value
 // Running expensive calculation...
@@ -276,7 +276,7 @@ 
println("Running expensive calculation...")
   1 + 2 * 3
 }
-// always: Eval[Int] = cats.Always@577258ed
+// always: Eval[Int] = cats.Always@26955ce1
 
 always.value
 // Running expensive calculation...
diff --git a/datatypes/freeapplicative.html b/datatypes/freeapplicative.html
index 933efaf2d3..4a2d09da6d 100644
--- a/datatypes/freeapplicative.html
+++ b/datatypes/freeapplicative.html
@@ -275,7 +275,7 @@ 
val validator = prog.foldMap[FromString](compiler)
-// validator: FromString[Boolean] = cats.instances.Function1Instances$$anon$7$$Lambda$11831/0x00007f929e031118@1d3aa811
+// validator: FromString[Boolean] = cats.instances.Function1Instances$$anon$7$$Lambda$14266/0x00007f75336c0bd0@4a651cc3
 validator("1234")
 // res0: Boolean = false
 validator("12345")
diff --git a/datatypes/freemonad.html b/datatypes/freemonad.html
index 2a8a5e5b0b..b35b7c7135 100644
--- a/datatypes/freemonad.html
+++ b/datatypes/freemonad.html
@@ -718,7 +718,7 @@ 
import TeletypeOps._
 
 val state = program.foldMap(interpreter)
-// state: TeletypeState[Unit] = cats.data.IndexedStateT@21cd5d7a
+// state: TeletypeState[Unit] = cats.data.IndexedStateT@5fe8c71a
 val initialState = Nil
 // initialState: Nil.type = List()
 val (stored, _) = state.run(initialState).value
@@ -789,7 +789,7 @@ 
val evaluated = hoisted.foldMap(tryInterpreter)
 // evaluated: OptTry[Int] = OptionT(value = Success(value = Some(value = 12)))
diff --git a/datatypes/state.html b/datatypes/state.html
index 6745e625ed..f748878880 100644
--- a/datatypes/state.html
+++ b/datatypes/state.html
@@ -474,7 +474,7 @@ 
_ <- close
   _ <- open
 } yield ()
-// valid: IndexedStateT[Eval, Closed.type, Open.type, Unit] = cats.data.IndexedStateT@73ddd481
+// valid: IndexedStateT[Eval, Closed.type, Open.type, Unit] = cats.data.IndexedStateT@2914197f

Note that the inferred type of valid correctly models that this computation can be executed only with an initial Closed state.

valid.run(Open)
 // error: type mismatch;
@@ -483,7 +483,7 @@ 
valid.run(Closed)
-// res6: Eval[(Open.type, Unit)] = cats.Eval$$anon$1@64b6383c
+// res6: Eval[(Open.type, Unit)] = cats.Eval$$anon$1@75cb5722
diff --git a/typeclasses/bifoldable.html b/typeclasses/bifoldable.html index 6c86e039f1..2cc2b9e047 100644 --- a/typeclasses/bifoldable.html +++ b/typeclasses/bifoldable.html @@ -338,7 +338,7 @@

s, acc) => acc.map(_ |+| s), (s, acc) => acc.map(_ |+| s) ) -// right: Eval[String] = cats.Eval$$anon$1@6cf139ee +// right: Eval[String] = cats.Eval$$anon$1@19614b44 left === expected // res2: Boolean = true @@ -354,7 +354,7 @@

s, acc) => acc.map(_ |+| s), (s, acc) => acc.map(_ |+| s) ) -// reversedRight: Eval[String] = cats.Eval$$anon$1@6ca64c53 +// reversedRight: Eval[String] = cats.Eval$$anon$1@431778fe reversedRight.value === expected // res4: Boolean = false diff --git a/typeclasses/bifunctor.html b/typeclasses/bifunctor.html index 08ee16e67c..5e1ba87626 100644 --- a/typeclasses/bifunctor.html +++ b/typeclasses/bifunctor.html @@ -246,7 +246,7 @@

error => DomainError(error.getMessage), dateTime => dateTime.toEpochSecond ) -// res0: Either[DomainError, Long] = Right(value = 1706939990L) +// res0: Either[DomainError, Long] = Right(value = 1706994037L)

Bifunctor also defines a convenience function called leftMap, which is defined as follows:

def leftMap[A, B, C](fab: F[A, B])(f: A => C): F[C, B] = bimap(fab)(f, identity)

There is no rightMap however - use map instead. The reasoning behind this is that in Cats, the instances of diff --git a/typeclasses/bimonad.html b/typeclasses/bimonad.html index e278f959e4..f75e7c5b6e 100644 --- a/typeclasses/bimonad.html +++ b/typeclasses/bimonad.html @@ -263,7 +263,7 @@

override def tailRecM[A, B](a: A)(fn: A => NonEmptyList[Either[A, B]]): NonEmptyList[B] = ??? } -// nelBimonad: Bimonad[NonEmptyList] = repl.MdocSession$MdocApp$$anon$1@6ff9352f +// nelBimonad: Bimonad[NonEmptyList] = repl.MdocSession$MdocApp$$anon$1@3f277f4

Note the equivalence:

nelBimonad.pure(true).extract === NonEmptyList.one(true).head
 // res0: Boolean = true
diff --git a/typeclasses/contravariant.html b/typeclasses/contravariant.html index 8eb1a782bd..db291c33be 100644 --- a/typeclasses/contravariant.html +++ b/typeclasses/contravariant.html @@ -246,7 +246,7 @@

implicit val showSalary: Show[Salary] = showMoney.contramap(_.size) -// showSalary: Show[Salary] = cats.Show$$anon$2$$Lambda$12603/0x00007f929e2ec6b8@40755e03 +// showSalary: Show[Salary] = cats.Show$$anon$2$$Lambda$15038/0x00007f753394f720@59d7258f Salary(Money(1000)).show // res0: String = "$1000" @@ -266,7 +266,7 @@

import scala.math.Ordered._ implicit val moneyOrdering: Ordering[Money] = Ordering.by(_.amount) -// moneyOrdering: Ordering[Money] = scala.math.Ordering$$anon$5@4aabc285 +// moneyOrdering: Ordering[Money] = scala.math.Ordering$$anon$5@347ae410 Money(100) < Money(200) // res3: Boolean = true @@ -276,17 +276,17 @@

class A class B extends A val b: B = new B -// b: B = repl.MdocSession$MdocApp$B@6415395f +// b: B = repl.MdocSession$MdocApp$B@70035f81 val a: A = b -// a: A = repl.MdocSession$MdocApp$B@6415395f +// a: A = repl.MdocSession$MdocApp$B@70035f81 val showA: Show[A] = Show.show(a => "a!") -// showA: Show[A] = cats.Show$$$Lambda$12602/0x00007f929e2ec240@67c78a0 +// showA: Show[A] = cats.Show$$$Lambda$15037/0x00007f753394f2a8@4a5b4cb val showB1: Show[B] = showA.contramap(b => b: A) -// showB1: Show[B] = cats.Show$$anon$2$$Lambda$12603/0x00007f929e2ec6b8@6c13ab2a +// showB1: Show[B] = cats.Show$$anon$2$$Lambda$15038/0x00007f753394f720@64be128d val showB2: Show[B] = showA.contramap(identity[A]) -// showB2: Show[B] = cats.Show$$anon$2$$Lambda$12603/0x00007f929e2ec6b8@7838f3c7 +// showB2: Show[B] = cats.Show$$anon$2$$Lambda$15038/0x00007f753394f720@707306e val showB3: Show[B] = Contravariant[Show].narrow[A, B](showA) -// showB3: Show[B] = cats.Show$$$Lambda$12602/0x00007f929e2ec240@67c78a0 +// showB3: Show[B] = cats.Show$$$Lambda$15037/0x00007f753394f2a8@4a5b4cb

Subtyping relationships are "lifted backwards" by contravariant functors, such that if F is a lawful contravariant functor and B <: A then F[A] <: F[B], which is expressed by Contravariant.narrow.

diff --git a/typeclasses/eq.html b/typeclasses/eq.html index e25e93caf8..9df640aec2 100644 --- a/typeclasses/eq.html +++ b/typeclasses/eq.html @@ -257,7 +257,7 @@

Eq

implicit val eqFoo: Eq[Foo] = Eq.fromUniversalEquals -// eqFoo: Eq[Foo] = cats.kernel.Eq$$anonfun$fromUniversalEquals$2@2b8f999d +// eqFoo: Eq[Foo] = cats.kernel.Eq$$anonfun$fromUniversalEquals$2@53a640d6 Foo(10, "") === Foo(10, "") diff --git a/typeclasses/foldable.html b/typeclasses/foldable.html index 3c04cccaf0..6c2843f1ad 100644 --- a/typeclasses/foldable.html +++ b/typeclasses/foldable.html @@ -301,7 +301,7 @@

Foldable

// res23: Option[Boolean] = Some(value = true) val prints: Eval[Unit] = List(Eval.always(println(1)), Eval.always(println(2))).sequence_ -// prints: Eval[Unit] = cats.Eval$$anon$4@2d59bc83 +// prints: Eval[Unit] = cats.Eval$$anon$4@27288361 prints.value Foldable[List].dropWhile_(List[Int](2,4,5,6,7))(_ % 2 == 0) diff --git a/typeclasses/semigroup.html b/typeclasses/semigroup.html index 523e929aae..944ad14401 100644 --- a/typeclasses/semigroup.html +++ b/typeclasses/semigroup.html @@ -269,23 +269,23 @@

import cats.Semigroup import cats.syntax.all._ 
Semigroup[Int]
-// res8: Semigroup[Int] = cats.kernel.instances.IntGroup@139986b5
+// res8: Semigroup[Int] = cats.kernel.instances.IntGroup@778d315c
 Semigroup[String]
-// res9: Semigroup[String] = cats.kernel.instances.StringMonoid@47c1649b
+// res9: Semigroup[String] = cats.kernel.instances.StringMonoid@1c318cc5

Instances for type constructors regardless of their type parameter such as List (++) and Set (union)...

Semigroup[List[Byte]]
-// res10: Semigroup[List[Byte]] = cats.kernel.instances.ListMonoid@159dea30
+// res10: Semigroup[List[Byte]] = cats.kernel.instances.ListMonoid@1e8b5e10
 Semigroup[Set[Int]]
-// res11: Semigroup[Set[Int]] = cats.kernel.instances.SetSemilattice@43b06752
+// res11: Semigroup[Set[Int]] = cats.kernel.instances.SetSemilattice@2e8a7fac
 
 trait Foo
 Semigroup[List[Foo]]
-// res12: Semigroup[List[Foo]] = cats.kernel.instances.ListMonoid@159dea30
+// res12: Semigroup[List[Foo]] = cats.kernel.instances.ListMonoid@1e8b5e10

And instances for type constructors that depend on (one of) their type parameters having instances such as tuples (pointwise combine).

Semigroup[(List[Foo], Int)]
-// res13: Semigroup[(List[Foo], Int)] = cats.kernel.Monoid$$anon$2@1cc3fdbf
+// res13: Semigroup[(List[Foo], Int)] = cats.kernel.Monoid$$anon$2@3013acf0

Example usage: Merging maps

Consider a function that merges two Maps that combines values if they share diff --git a/typeclasses/show.html b/typeclasses/show.html index e8745a513a..c454748ca4 100644 --- a/typeclasses/show.html +++ b/typeclasses/show.html @@ -229,7 +229,7 @@

Show

Most often, this is unwanted behaviour, as the standard implementation of toString on non case classes is mostly gibberish. Consider the following example:

(new {}).toString
-// res0: String = "repl.MdocSession$MdocApp$$anon$1@7ccd7216"
+// res0: String = "repl.MdocSession$MdocApp$$anon$1@270699cf"

The fact that this code compiles is a design flaw of the Java API. We want to make things like this impossible, by offering the toString equivalent as a type class, instead of the root of the class hierarchy. In short, Show allows us to only have String-conversions defined for the data types we actually want.

@@ -245,12 +245,12 @@

Show

case class Person(name: String, age: Int) implicit val showPerson: Show[Person] = Show.show(person => person.name) -// showPerson: Show[Person] = cats.Show$$$Lambda$12602/0x00007f929e2ec240@88ab930 +// showPerson: Show[Person] = cats.Show$$$Lambda$15037/0x00007f753394f2a8@3372f43c case class Department(id: Int, name: String) implicit val showDep: Show[Department] = Show.fromToString -// showDep: Show[Department] = cats.Show$$$Lambda$11670/0x00007f929df7cc90@4e219f3c +// showDep: Show[Department] = cats.Show$$$Lambda$14105/0x00007f753360d290@eabae2c

This still may not seem useful to you, because case classes already automatically implement toString, while show would have to be implemented manually for each case class. Thankfully with the help of a small library called kittens a lot of type class instances including Show can be derived automatically!

Cats also offers Show syntax to make working with it easier.