Prism: change fromNullable signature

gcanti · Jul 13, 2020 · 74dba26 · 74dba26
1 parent ecd5a36
commit 74dba26
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diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -17,7 +17,10 @@ high state of flux, you're at risk of it changing without notice.
 
 - **Experimental**
   - `Prism`
-    - remove `fromSome` constructor (@gcanti)
+    - (\*) remove `fromSome` constructor (@gcanti)
+    - (\*) change `fromNullable` signature (@gcanti)
+
+(\*) breaking change
 
 # 2.3.2
 

diff --git a/docs/modules/Lens.ts.md b/docs/modules/Lens.ts.md
@@ -36,6 +36,7 @@ Added in v2.3.0
   - [component](#component)
   - [filter](#filter)
   - [findFirst](#findfirst)
+  - [fromNullable](#fromnullable)
   - [index](#index)
   - [key](#key)
   - [left](#left)
@@ -50,7 +51,6 @@ Added in v2.3.0
   - [composeOptional](#composeoptional)
   - [composePrism](#composeprism)
 - [constructors](#constructors)
-  - [fromNullable](#fromnullable)
   - [id](#id)
 - [converters](#converters)
   - [asOptional](#asoptional)
@@ -126,6 +126,18 @@ export declare const findFirst: <A>(predicate: Predicate<A>) => <S>(sa: Lens<S,
 
 Added in v2.3.2
 
+## fromNullable
+
+Return a `Optional` from a `Lens` focused on a nullable value
+
+**Signature**
+
+```ts
+export declare const fromNullable: <S, A>(sa: Lens<S, A>) => Optional<S, NonNullable<A>>
+```
+
+Added in v2.3.0
+
 ## index
 
 Return a `Optional` from a `Lens` focused on a `ReadonlyArray`
@@ -278,18 +290,6 @@ Added in v2.3.0
 
 # constructors
 
-## fromNullable
-
-Return a `Optional` from a `Lens` focused on a nullable value
-
-**Signature**
-
-```ts
-export declare const fromNullable: <S, A>(sa: Lens<S, A>) => Optional<S, NonNullable<A>>
-```
-
-Added in v2.3.0
-
 ## id
 
 **Signature**

diff --git a/docs/modules/Prism.ts.md b/docs/modules/Prism.ts.md
@@ -32,6 +32,7 @@ Added in v2.3.0
   - [component](#component)
   - [filter](#filter)
   - [findFirst](#findfirst)
+  - [fromNullable](#fromnullable)
   - [index](#index)
   - [key](#key)
   - [left](#left)
@@ -48,7 +49,6 @@ Added in v2.3.0
   - [composeLens](#composelens)
   - [composeOptional](#composeoptional)
 - [constructors](#constructors)
-  - [fromNullable](#fromnullable)
   - [fromPredicate](#frompredicate)
   - [id](#id)
 - [converters](#converters)
@@ -127,6 +127,18 @@ export declare const findFirst: <A>(predicate: Predicate<A>) => <S>(sa: Prism<S,
 
 Added in v2.3.2
 
+## fromNullable
+
+Return a `Prism` from a `Prism` focused on a nullable value
+
+**Signature**
+
+```ts
+export declare const fromNullable: <S, A>(sa: Prism<S, A>) => Prism<S, NonNullable<A>>
+```
+
+Added in v2.3.3
+
 ## index
 
 Return a `Optional` from a `Prism` focused on a `ReadonlyArray`
@@ -299,16 +311,6 @@ Added in v2.3.0
 
 # constructors
 
-## fromNullable
-
-**Signature**
-
-```ts
-export declare const fromNullable: <A>() => Prism<A, NonNullable<A>>
-```
-
-Added in v2.3.0
-
 ## fromPredicate
 
 **Signature**

diff --git a/src/Lens.ts b/src/Lens.ts
@@ -120,7 +120,7 @@ export const modify = <A>(f: (a: A) => A) => <S>(sa: Lens<S, A>) => (s: S): S =>
 /**
  * Return a `Optional` from a `Lens` focused on a nullable value
  *
- * @category constructors
+ * @category combinators
  * @since 2.3.0
  */
 export const fromNullable = <S, A>(sa: Lens<S, A>): Optional<S, NonNullable<A>> =>

diff --git a/src/Prism.ts b/src/Prism.ts
@@ -64,12 +64,6 @@ export const fromPredicate: {
   <A>(predicate: Predicate<A>): Prism<A, A>
 } = _.prismFromPredicate
 
-/**
- * @category constructors
- * @since 2.3.0
- */
-export const fromNullable: <A>() => Prism<A, NonNullable<A>> = _.prismFromNullable
-
 // -------------------------------------------------------------------------------------
 // converters
 // -------------------------------------------------------------------------------------
@@ -138,6 +132,16 @@ export const modifyOption: <A>(f: (a: A) => A) => <S>(sa: Prism<S, A>) => (s: S)
  */
 export const modify: <A>(f: (a: A) => A) => <S>(sa: Prism<S, A>) => (s: S) => S = _.prismModify
 
+/**
+ * Return a `Prism` from a `Prism` focused on a nullable value
+ *
+ * @category combinators
+ * @since 2.3.3
+ */
+export const fromNullable: <S, A>(sa: Prism<S, A>) => Prism<S, NonNullable<A>> =
+  /*#__PURE__*/
+  compose(_.prismFromNullable())
+
 /**
  * @category combinators
  * @since 2.3.0

diff --git a/test/Prism.ts b/test/Prism.ts
@@ -208,4 +208,13 @@ describe('Prism', () => {
     )
     assert.deepStrictEqual(modify(O.some(['a'])), O.some(['A']))
   })
+
+  it('fromNullable', () => {
+    type S = O.Option<number | undefined>
+    const sa = pipe(_.id<S>(), _.some, _.fromNullable)
+    assert.deepStrictEqual(sa.getOption(O.none), O.none)
+    assert.deepStrictEqual(sa.getOption(O.some(undefined)), O.none)
+    assert.deepStrictEqual(sa.getOption(O.some(1)), O.some(1))
+    assert.deepStrictEqual(sa.reverseGet(1), O.some(1))
+  })
 })