From a882beb83a7574abe28de10e437ba954b6792dd8 Mon Sep 17 00:00:00 2001
From: glennsl <glenn@slotte.net>
Date: Sat, 18 Feb 2023 14:20:06 +0100
Subject: [PATCH 01/18] feat(array): add findMap

---
 src/Core__Array.mjs  | 17 +++++++++++++++++
 src/Core__Array.res  | 14 ++++++++++++++
 src/Core__Array.resi |  3 ++-
 3 files changed, 33 insertions(+), 1 deletion(-)

diff --git a/src/Core__Array.mjs b/src/Core__Array.mjs
index f675dff5..6de9103f 100644
--- a/src/Core__Array.mjs
+++ b/src/Core__Array.mjs
@@ -112,6 +112,22 @@ function flatMap(a, f) {
   return Caml_splice_call.spliceObjApply([], "concat", [a.map(f)]);
 }
 
+function findMap(arr, f) {
+  var _i = 0;
+  while(true) {
+    var i = _i;
+    if (i === arr.length) {
+      return ;
+    }
+    var r = Curry._1(f, arr[i]);
+    if (r !== undefined) {
+      return r;
+    }
+    _i = i + 1 | 0;
+    continue ;
+  };
+}
+
 export {
   sort ,
   indexOfOpt ,
@@ -125,5 +141,6 @@ export {
   shuffle ,
   shuffleInPlace ,
   flatMap ,
+  findMap ,
 }
 /* No side effect */
diff --git a/src/Core__Array.res b/src/Core__Array.res
index 658f45c8..c2b3db18 100644
--- a/src/Core__Array.res
+++ b/src/Core__Array.res
@@ -203,4 +203,18 @@ let filterMap = (a, f) => filterMapU(a, (. a) => f(a))
 // TODO: Change this implementation?
 let flatMap = (a, f) => []->concatMany(map(a, f))
 
+let findMap = (arr, f) => {
+  let rec loop = i =>
+    if i == arr->length {
+      None
+    } else {
+      switch f(getUnsafe(arr, i)) {
+      | None => loop(i + 1)
+      | Some(_) as r => r
+      }
+    }
+
+  loop(0)
+}
+
 @send external at: (array<'a>, int) => option<'a> = "at"
diff --git a/src/Core__Array.resi b/src/Core__Array.resi
index 562f739d..71030b0e 100644
--- a/src/Core__Array.resi
+++ b/src/Core__Array.resi
@@ -104,8 +104,9 @@ let filterMap: (array<'a>, 'a => option<'b>) => array<'b>
 let shuffle: array<'a> => array<'a>
 let shuffleInPlace: array<'a> => unit
 let flatMap: (array<'a>, 'a => array<'b>) => array<'b>
+let findMap: (array<'a>, 'a => option<'b>) => option<'b>
 
-/** 
+/**
   `at(array, index)`
 
   Get an element by its index. Negative indices count backwards from the last item.

From 31c8f64f6f8c3b65648746a3d1a31a436d6011e5 Mon Sep 17 00:00:00 2001
From: glennsl <glenn@slotte.net>
Date: Sat, 18 Feb 2023 15:01:55 +0100
Subject: [PATCH 02/18] feat(array): add init

---
 src/Core__Array.mjs  | 12 ++++++++++++
 src/Core__Array.res  | 15 +++++++++++++--
 src/Core__Array.resi |  1 +
 3 files changed, 26 insertions(+), 2 deletions(-)

diff --git a/src/Core__Array.mjs b/src/Core__Array.mjs
index 6de9103f..8383af8a 100644
--- a/src/Core__Array.mjs
+++ b/src/Core__Array.mjs
@@ -5,6 +5,17 @@ import * as Js_math from "rescript/lib/es6/js_math.js";
 import * as Caml_option from "rescript/lib/es6/caml_option.js";
 import * as Caml_splice_call from "rescript/lib/es6/caml_splice_call.js";
 
+function init(len, f) {
+  if (len <= 0) {
+    return [];
+  }
+  var arr = new Array(len);
+  for(var i = 0; i < len; ++i){
+    arr[i] = Curry._1(f, i);
+  }
+  return arr;
+}
+
 function indexOfOpt(arr, item) {
   var index = arr.indexOf(item);
   if (index !== -1) {
@@ -129,6 +140,7 @@ function findMap(arr, f) {
 }
 
 export {
+  init ,
   sort ,
   indexOfOpt ,
   lastIndexOfOpt ,
diff --git a/src/Core__Array.res b/src/Core__Array.res
index c2b3db18..5ed477e6 100644
--- a/src/Core__Array.res
+++ b/src/Core__Array.res
@@ -1,3 +1,5 @@
+@new external makeUninitializedUnsafe: int => array<'a> = "Array"
+@set external truncateToLengthUnsafe: (array<'a>, int) => unit = "length"
 external getUnsafe: (array<'a>, int) => 'a = "%array_unsafe_get"
 external setUnsafe: (array<'a>, int, 'a) => unit = "%array_unsafe_set"
 
@@ -11,6 +13,17 @@ external fromArrayLikeWithMap: (Js.Array2.array_like<'a>, 'a => 'b) => array<'b>
 @val external fromIterator: Core__Iterator.t<'a> => array<'a> = "Array.from"
 @val external fromIteratorWithMap: (Core__Iterator.t<'a>, 'a => 'b) => array<'b> = "Array.from"
 
+let init = (len, f) =>
+  if len <= 0 {
+    []
+  } else {
+    let arr = makeUninitializedUnsafe(len)
+    for i in 0 to len - 1 {
+      arr->setUnsafe(i, f(i))
+    }
+    arr
+  }
+
 @val external isArray: 'a => bool = "Array.isArray"
 
 @get external length: array<'a> => int = "length"
@@ -151,8 +164,6 @@ let findIndexOpt = (array: array<'a>, finder: 'a => bool): option<int> =>
   | index => Some(index)
   }
 
-@new external makeUninitializedUnsafe: int => array<'a> = "Array"
-@set external truncateToLengthUnsafe: (array<'a>, int) => unit = "length"
 let swapUnsafe = (xs, i, j) => {
   let tmp = getUnsafe(xs, i)
   setUnsafe(xs, i, getUnsafe(xs, j))
diff --git a/src/Core__Array.resi b/src/Core__Array.resi
index 71030b0e..1d991537 100644
--- a/src/Core__Array.resi
+++ b/src/Core__Array.resi
@@ -5,6 +5,7 @@
 external fromArrayLikeWithMap: (Js.Array2.array_like<'a>, 'a => 'b) => array<'b> = "Array.from"
 @val external fromIterator: Core__Iterator.t<'a> => array<'a> = "Array.from"
 @val external fromIteratorWithMap: (Core__Iterator.t<'a>, 'a => 'b) => array<'b> = "Array.from"
+let init: (int, int => 'a) => array<'a>
 @val external isArray: 'a => bool = "Array.isArray"
 @get external length: array<'a> => int = "length"
 @send external copyAllWithin: (array<'a>, ~target: int) => array<'a> = "copyWithin"

From 307da8955fee223ae55fd37befda7ee02be3ff1f Mon Sep 17 00:00:00 2001
From: glennsl <glenn@slotte.net>
Date: Sat, 18 Feb 2023 15:04:37 +0100
Subject: [PATCH 03/18] feat(array): add make

---
 src/Core__Array.mjs  | 12 ++++++++++++
 src/Core__Array.res  | 11 +++++++++++
 src/Core__Array.resi |  1 +
 3 files changed, 24 insertions(+)

diff --git a/src/Core__Array.mjs b/src/Core__Array.mjs
index 8383af8a..65376042 100644
--- a/src/Core__Array.mjs
+++ b/src/Core__Array.mjs
@@ -5,6 +5,17 @@ import * as Js_math from "rescript/lib/es6/js_math.js";
 import * as Caml_option from "rescript/lib/es6/caml_option.js";
 import * as Caml_splice_call from "rescript/lib/es6/caml_splice_call.js";
 
+function make(len, x) {
+  if (len <= 0) {
+    return [];
+  }
+  var arr = new Array(len);
+  for(var i = 0; i < len; ++i){
+    arr[i] = x;
+  }
+  return arr;
+}
+
 function init(len, f) {
   if (len <= 0) {
     return [];
@@ -140,6 +151,7 @@ function findMap(arr, f) {
 }
 
 export {
+  make ,
   init ,
   sort ,
   indexOfOpt ,
diff --git a/src/Core__Array.res b/src/Core__Array.res
index 5ed477e6..e32adddf 100644
--- a/src/Core__Array.res
+++ b/src/Core__Array.res
@@ -13,6 +13,17 @@ external fromArrayLikeWithMap: (Js.Array2.array_like<'a>, 'a => 'b) => array<'b>
 @val external fromIterator: Core__Iterator.t<'a> => array<'a> = "Array.from"
 @val external fromIteratorWithMap: (Core__Iterator.t<'a>, 'a => 'b) => array<'b> = "Array.from"
 
+let make = (len, x) =>
+  if len <= 0 {
+    []
+  } else {
+    let arr = makeUninitializedUnsafe(len)
+    for i in 0 to len - 1 {
+      arr->setUnsafe(i, x)
+    }
+    arr
+  }
+
 let init = (len, f) =>
   if len <= 0 {
     []
diff --git a/src/Core__Array.resi b/src/Core__Array.resi
index 1d991537..00f581c0 100644
--- a/src/Core__Array.resi
+++ b/src/Core__Array.resi
@@ -5,6 +5,7 @@
 external fromArrayLikeWithMap: (Js.Array2.array_like<'a>, 'a => 'b) => array<'b> = "Array.from"
 @val external fromIterator: Core__Iterator.t<'a> => array<'a> = "Array.from"
 @val external fromIteratorWithMap: (Core__Iterator.t<'a>, 'a => 'b) => array<'b> = "Array.from"
+let make: (int, 'a) => array<'a>
 let init: (int, int => 'a) => array<'a>
 @val external isArray: 'a => bool = "Array.isArray"
 @get external length: array<'a> => int = "length"

From 12402ae2b4df64c2cf92ed142ccf78e2609cd889 Mon Sep 17 00:00:00 2001
From: glennsl <glenn@slotte.net>
Date: Sat, 18 Feb 2023 15:15:25 +0100
Subject: [PATCH 04/18] feat(array): add keepSome

---
 src/Core__Array.mjs  | 7 +++++++
 src/Core__Array.res  | 2 ++
 src/Core__Array.resi | 1 +
 3 files changed, 10 insertions(+)

diff --git a/src/Core__Array.mjs b/src/Core__Array.mjs
index 65376042..951e01bf 100644
--- a/src/Core__Array.mjs
+++ b/src/Core__Array.mjs
@@ -130,6 +130,12 @@ function filterMap(a, f) {
   return r;
 }
 
+function keepSome(__x) {
+  return filterMap(__x, (function (x) {
+                return x;
+              }));
+}
+
 function flatMap(a, f) {
   return Caml_splice_call.spliceObjApply([], "concat", [a.map(f)]);
 }
@@ -162,6 +168,7 @@ export {
   findIndexOpt ,
   reverse ,
   filterMap ,
+  keepSome ,
   shuffle ,
   shuffleInPlace ,
   flatMap ,
diff --git a/src/Core__Array.res b/src/Core__Array.res
index e32adddf..c4ca2777 100644
--- a/src/Core__Array.res
+++ b/src/Core__Array.res
@@ -222,6 +222,8 @@ let filterMapU = (a, f) => {
 
 let filterMap = (a, f) => filterMapU(a, (. a) => f(a))
 
+let keepSome = filterMap(_, x => x)
+
 // TODO: Change this implementation?
 let flatMap = (a, f) => []->concatMany(map(a, f))
 
diff --git a/src/Core__Array.resi b/src/Core__Array.resi
index 00f581c0..909a43d8 100644
--- a/src/Core__Array.resi
+++ b/src/Core__Array.resi
@@ -103,6 +103,7 @@ external setUnsafe: (array<'a>, int, 'a) => unit = "%array_unsafe_set"
 let findIndexOpt: (array<'a>, 'a => bool) => option<int>
 let reverse: array<'a> => array<'a>
 let filterMap: (array<'a>, 'a => option<'b>) => array<'b>
+let keepSome: array<option<'a>> => array<'a>
 let shuffle: array<'a> => array<'a>
 let shuffleInPlace: array<'a> => unit
 let flatMap: (array<'a>, 'a => array<'b>) => array<'b>

From 2370ea64aa3f17a9fcbdc051fe49d7090c13cd10 Mon Sep 17 00:00:00 2001
From: glennsl <glenn@slotte.net>
Date: Sat, 18 Feb 2023 16:33:02 +0100
Subject: [PATCH 05/18] refactor(array): bind to flatMap instead of
 reimplementing it

---
 src/Core__Array.mjs  | 6 ------
 src/Core__Array.res  | 3 +--
 src/Core__Array.resi | 2 +-
 3 files changed, 2 insertions(+), 9 deletions(-)

diff --git a/src/Core__Array.mjs b/src/Core__Array.mjs
index 951e01bf..052551be 100644
--- a/src/Core__Array.mjs
+++ b/src/Core__Array.mjs
@@ -3,7 +3,6 @@
 import * as Curry from "rescript/lib/es6/curry.js";
 import * as Js_math from "rescript/lib/es6/js_math.js";
 import * as Caml_option from "rescript/lib/es6/caml_option.js";
-import * as Caml_splice_call from "rescript/lib/es6/caml_splice_call.js";
 
 function make(len, x) {
   if (len <= 0) {
@@ -136,10 +135,6 @@ function keepSome(__x) {
               }));
 }
 
-function flatMap(a, f) {
-  return Caml_splice_call.spliceObjApply([], "concat", [a.map(f)]);
-}
-
 function findMap(arr, f) {
   var _i = 0;
   while(true) {
@@ -171,7 +166,6 @@ export {
   keepSome ,
   shuffle ,
   shuffleInPlace ,
-  flatMap ,
   findMap ,
 }
 /* No side effect */
diff --git a/src/Core__Array.res b/src/Core__Array.res
index c4ca2777..d45d9056 100644
--- a/src/Core__Array.res
+++ b/src/Core__Array.res
@@ -224,8 +224,7 @@ let filterMap = (a, f) => filterMapU(a, (. a) => f(a))
 
 let keepSome = filterMap(_, x => x)
 
-// TODO: Change this implementation?
-let flatMap = (a, f) => []->concatMany(map(a, f))
+@send external flatMap: (array<'a>, 'a => array<'b>) => array<'b> = "flatMap"
 
 let findMap = (arr, f) => {
   let rec loop = i =>
diff --git a/src/Core__Array.resi b/src/Core__Array.resi
index 909a43d8..4456ecd9 100644
--- a/src/Core__Array.resi
+++ b/src/Core__Array.resi
@@ -106,7 +106,7 @@ let filterMap: (array<'a>, 'a => option<'b>) => array<'b>
 let keepSome: array<option<'a>> => array<'a>
 let shuffle: array<'a> => array<'a>
 let shuffleInPlace: array<'a> => unit
-let flatMap: (array<'a>, 'a => array<'b>) => array<'b>
+@send external flatMap: (array<'a>, 'a => array<'b>) => array<'b> = "flatMap"
 let findMap: (array<'a>, 'a => option<'b>) => option<'b>
 
 /**

From aa0607865840a6a53e75fd175d687353dad2cc2e Mon Sep 17 00:00:00 2001
From: glennsl <glenn@slotte.net>
Date: Sat, 18 Feb 2023 21:45:35 +0100
Subject: [PATCH 06/18] refactor(array/make): use fillAllInPlace instead of
 manual loop

---
 src/Core__Array.mjs |  4 +---
 src/Core__Array.res | 16 +++++++---------
 2 files changed, 8 insertions(+), 12 deletions(-)

diff --git a/src/Core__Array.mjs b/src/Core__Array.mjs
index 052551be..169799c3 100644
--- a/src/Core__Array.mjs
+++ b/src/Core__Array.mjs
@@ -9,9 +9,7 @@ function make(len, x) {
     return [];
   }
   var arr = new Array(len);
-  for(var i = 0; i < len; ++i){
-    arr[i] = x;
-  }
+  arr.fill(x);
   return arr;
 }
 
diff --git a/src/Core__Array.res b/src/Core__Array.res
index d45d9056..b8047d1f 100644
--- a/src/Core__Array.res
+++ b/src/Core__Array.res
@@ -13,14 +13,18 @@ external fromArrayLikeWithMap: (Js.Array2.array_like<'a>, 'a => 'b) => array<'b>
 @val external fromIterator: Core__Iterator.t<'a> => array<'a> = "Array.from"
 @val external fromIteratorWithMap: (Core__Iterator.t<'a>, 'a => 'b) => array<'b> = "Array.from"
 
+@send external fillAllInPlace: (array<'a>, 'a) => unit = "fill"
+
+@send external fillInPlaceToEnd: (array<'a>, 'a, ~start: int) => unit = "fill"
+
+@send external fillInPlace: (array<'a>, 'a, ~start: int, ~end: int) => unit = "fill"
+
 let make = (len, x) =>
   if len <= 0 {
     []
   } else {
     let arr = makeUninitializedUnsafe(len)
-    for i in 0 to len - 1 {
-      arr->setUnsafe(i, x)
-    }
+    arr->fillAllInPlace(x)
     arr
   }
 
@@ -47,12 +51,6 @@ external copyWithinToEnd: (array<'a>, ~target: int, ~start: int) => array<'a> =
 @send
 external copyWithin: (array<'a>, ~target: int, ~start: int, ~end: int) => array<'a> = "copyWithin"
 
-@send external fillAllInPlace: (array<'a>, 'a) => unit = "fill"
-
-@send external fillInPlaceToEnd: (array<'a>, 'a, ~start: int) => unit = "fill"
-
-@send external fillInPlace: (array<'a>, 'a, ~start: int, ~end: int) => unit = "fill"
-
 @send external pop: array<'a> => option<'a> = "pop"
 
 @send external push: (array<'a>, 'a) => unit = "push"

From e02724ce7c31b21ab219f00ec4bee81a5f0323ae Mon Sep 17 00:00:00 2001
From: glennsl <glenn@slotte.net>
Date: Sun, 19 Feb 2023 20:13:37 +0100
Subject: [PATCH 07/18] feat(array): use labelled argument for length in make
 and init

---
 src/Core__Array.mjs  | 14 +++++++-------
 src/Core__Array.res  | 14 +++++++-------
 src/Core__Array.resi |  4 ++--
 3 files changed, 16 insertions(+), 16 deletions(-)

diff --git a/src/Core__Array.mjs b/src/Core__Array.mjs
index 169799c3..741b1a79 100644
--- a/src/Core__Array.mjs
+++ b/src/Core__Array.mjs
@@ -4,21 +4,21 @@ import * as Curry from "rescript/lib/es6/curry.js";
 import * as Js_math from "rescript/lib/es6/js_math.js";
 import * as Caml_option from "rescript/lib/es6/caml_option.js";
 
-function make(len, x) {
-  if (len <= 0) {
+function make(length, x) {
+  if (length <= 0) {
     return [];
   }
-  var arr = new Array(len);
+  var arr = new Array(length);
   arr.fill(x);
   return arr;
 }
 
-function init(len, f) {
-  if (len <= 0) {
+function init(length, f) {
+  if (length <= 0) {
     return [];
   }
-  var arr = new Array(len);
-  for(var i = 0; i < len; ++i){
+  var arr = new Array(length);
+  for(var i = 0; i < length; ++i){
     arr[i] = Curry._1(f, i);
   }
   return arr;
diff --git a/src/Core__Array.res b/src/Core__Array.res
index b8047d1f..8fb68189 100644
--- a/src/Core__Array.res
+++ b/src/Core__Array.res
@@ -19,21 +19,21 @@ external fromArrayLikeWithMap: (Js.Array2.array_like<'a>, 'a => 'b) => array<'b>
 
 @send external fillInPlace: (array<'a>, 'a, ~start: int, ~end: int) => unit = "fill"
 
-let make = (len, x) =>
-  if len <= 0 {
+let make = (~length, x) =>
+  if length <= 0 {
     []
   } else {
-    let arr = makeUninitializedUnsafe(len)
+    let arr = makeUninitializedUnsafe(length)
     arr->fillAllInPlace(x)
     arr
   }
 
-let init = (len, f) =>
-  if len <= 0 {
+let init = (~length, f) =>
+  if length <= 0 {
     []
   } else {
-    let arr = makeUninitializedUnsafe(len)
-    for i in 0 to len - 1 {
+    let arr = makeUninitializedUnsafe(length)
+    for i in 0 to length - 1 {
       arr->setUnsafe(i, f(i))
     }
     arr
diff --git a/src/Core__Array.resi b/src/Core__Array.resi
index 4456ecd9..dac621aa 100644
--- a/src/Core__Array.resi
+++ b/src/Core__Array.resi
@@ -5,8 +5,8 @@
 external fromArrayLikeWithMap: (Js.Array2.array_like<'a>, 'a => 'b) => array<'b> = "Array.from"
 @val external fromIterator: Core__Iterator.t<'a> => array<'a> = "Array.from"
 @val external fromIteratorWithMap: (Core__Iterator.t<'a>, 'a => 'b) => array<'b> = "Array.from"
-let make: (int, 'a) => array<'a>
-let init: (int, int => 'a) => array<'a>
+let make: (~length: int, 'a) => array<'a>
+let init: (~length: int, int => 'a) => array<'a>
 @val external isArray: 'a => bool = "Array.isArray"
 @get external length: array<'a> => int = "length"
 @send external copyAllWithin: (array<'a>, ~target: int) => array<'a> = "copyWithin"

From c8a67b5c5111adc5599c5f4acfff5b862296d237 Mon Sep 17 00:00:00 2001
From: glennsl <glenn@slotte.net>
Date: Sun, 19 Feb 2023 20:15:04 +0100
Subject: [PATCH 08/18] refactor(array): rename init -> fromInitializer

---
 src/Core__Array.mjs  | 4 ++--
 src/Core__Array.res  | 2 +-
 src/Core__Array.resi | 2 +-
 3 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/Core__Array.mjs b/src/Core__Array.mjs
index 741b1a79..debbd163 100644
--- a/src/Core__Array.mjs
+++ b/src/Core__Array.mjs
@@ -13,7 +13,7 @@ function make(length, x) {
   return arr;
 }
 
-function init(length, f) {
+function fromInitializer(length, f) {
   if (length <= 0) {
     return [];
   }
@@ -151,7 +151,7 @@ function findMap(arr, f) {
 
 export {
   make ,
-  init ,
+  fromInitializer ,
   sort ,
   indexOfOpt ,
   lastIndexOfOpt ,
diff --git a/src/Core__Array.res b/src/Core__Array.res
index 8fb68189..77c3297d 100644
--- a/src/Core__Array.res
+++ b/src/Core__Array.res
@@ -28,7 +28,7 @@ let make = (~length, x) =>
     arr
   }
 
-let init = (~length, f) =>
+let fromInitializer = (~length, f) =>
   if length <= 0 {
     []
   } else {
diff --git a/src/Core__Array.resi b/src/Core__Array.resi
index dac621aa..11457d5f 100644
--- a/src/Core__Array.resi
+++ b/src/Core__Array.resi
@@ -6,7 +6,7 @@ external fromArrayLikeWithMap: (Js.Array2.array_like<'a>, 'a => 'b) => array<'b>
 @val external fromIterator: Core__Iterator.t<'a> => array<'a> = "Array.from"
 @val external fromIteratorWithMap: (Core__Iterator.t<'a>, 'a => 'b) => array<'b> = "Array.from"
 let make: (~length: int, 'a) => array<'a>
-let init: (~length: int, int => 'a) => array<'a>
+let fromInitializer: (~length: int, int => 'a) => array<'a>
 @val external isArray: 'a => bool = "Array.isArray"
 @get external length: array<'a> => int = "length"
 @send external copyAllWithin: (array<'a>, ~target: int) => array<'a> = "copyWithin"

From 93110d08c642c3791f41fe3b8ed898b7c4f3bfd3 Mon Sep 17 00:00:00 2001
From: glennsl <glenn@slotte.net>
Date: Sun, 26 Feb 2023 15:11:19 +0100
Subject: [PATCH 09/18] test(array): add tests for non-native functions

---
 package.json        |   6 +-
 test/ArrayTests.mjs | 321 ++++++++++++++++++++++++++++++++++++++++++++
 test/ArrayTests.res |  74 ++++++++++
 test/TestSuite.mjs  |  35 +++++
 test/TestSuite.res  |   2 +
 5 files changed, 434 insertions(+), 4 deletions(-)
 create mode 100644 test/ArrayTests.mjs
 create mode 100644 test/ArrayTests.res
 create mode 100644 test/TestSuite.mjs
 create mode 100644 test/TestSuite.res

diff --git a/package.json b/package.json
index d23f0f91..f4a3fb7b 100644
--- a/package.json
+++ b/package.json
@@ -5,11 +5,9 @@
     "clean": "rescript clean",
     "build": "rescript",
     "watch": "rescript build -w",
-    "test": "node test/PromiseTest.mjs && node test/TempTests.mjs"
+    "test": "node test/TestSuite.mjs && node test/TempTests.mjs"
   },
-  "keywords": [
-    "rescript"
-  ],
+  "keywords": ["rescript"],
   "homepage": "https://github.com/rescript-association/rescript-core",
   "author": "ReScript Team",
   "license": "MIT",
diff --git a/test/ArrayTests.mjs b/test/ArrayTests.mjs
new file mode 100644
index 00000000..bc52af57
--- /dev/null
+++ b/test/ArrayTests.mjs
@@ -0,0 +1,321 @@
+// Generated by ReScript, PLEASE EDIT WITH CARE
+
+import * as Test from "./Test.mjs";
+import * as Caml_obj from "rescript/lib/es6/caml_obj.js";
+import * as Core__List from "../src/Core__List.mjs";
+import * as Core__Array from "../src/Core__Array.mjs";
+
+var eq = Caml_obj.equal;
+
+Test.run([
+      [
+        "ArrayTests.res",
+        5,
+        20,
+        26
+      ],
+      "make"
+    ], Core__Array.make(6, 7), eq, [
+      7,
+      7,
+      7,
+      7,
+      7,
+      7
+    ]);
+
+Test.run([
+      [
+        "ArrayTests.res",
+        8,
+        13,
+        30
+      ],
+      "fromInitializer"
+    ], Core__Array.fromInitializer(7, (function (i) {
+            return i + 3 | 0;
+          })), eq, [
+      3,
+      4,
+      5,
+      6,
+      7,
+      8,
+      9
+    ]);
+
+Test.run([
+      [
+        "ArrayTests.res",
+        14,
+        20,
+        28
+      ],
+      "reduce"
+    ], Core__Array.reduce([
+          1,
+          2,
+          3
+        ], /* [] */0, Core__List.add), eq, {
+      hd: 3,
+      tl: {
+        hd: 2,
+        tl: {
+          hd: 1,
+          tl: /* [] */0
+        }
+      }
+    });
+
+Test.run([
+      [
+        "ArrayTests.res",
+        15,
+        20,
+        36
+      ],
+      "reduce - empty"
+    ], Core__Array.reduce([], /* [] */0, Core__List.add), eq, /* [] */0);
+
+Test.run([
+      [
+        "ArrayTests.res",
+        18,
+        13,
+        28
+      ],
+      "reduceReverse"
+    ], Core__Array.reduceReverse([
+          1,
+          2,
+          3
+        ], /* [] */0, Core__List.add), eq, {
+      hd: 1,
+      tl: {
+        hd: 2,
+        tl: {
+          hd: 3,
+          tl: /* [] */0
+        }
+      }
+    });
+
+Test.run([
+      [
+        "ArrayTests.res",
+        23,
+        20,
+        43
+      ],
+      "reduceReverse - empty"
+    ], Core__Array.reduceReverse([], /* [] */0, Core__List.add), eq, /* [] */0);
+
+Test.run([
+      [
+        "ArrayTests.res",
+        25,
+        20,
+        38
+      ],
+      "shuffle - length"
+    ], Core__Array.shuffle([
+          1,
+          2,
+          3
+        ]).length, eq, 3);
+
+var arr = [
+  1,
+  2,
+  3
+];
+
+Test.run([
+      [
+        "ArrayTests.res",
+        28,
+        13,
+        38
+      ],
+      "shuffleInPlace - length"
+    ], (Core__Array.shuffleInPlace(arr), arr.length), eq, 3);
+
+Test.run([
+      [
+        "ArrayTests.res",
+        39,
+        13,
+        24
+      ],
+      "filterMap"
+    ], Core__Array.filterMap([
+          1,
+          2,
+          3,
+          4,
+          5,
+          6
+        ], (function (n) {
+            if (n % 2 === 0) {
+              return Math.imul(n, n);
+            }
+            
+          })), eq, [
+      4,
+      16,
+      36
+    ]);
+
+Test.run([
+      [
+        "ArrayTests.res",
+        44,
+        20,
+        42
+      ],
+      "filterMap - no match"
+    ], Core__Array.filterMap([
+          1,
+          2,
+          3,
+          4,
+          5,
+          6
+        ], (function (param) {
+            
+          })), eq, []);
+
+Test.run([
+      [
+        "ArrayTests.res",
+        46,
+        13,
+        32
+      ],
+      "filterMap - empty"
+    ], Core__Array.filterMap([], (function (n) {
+            if (n % 2 === 0) {
+              return Math.imul(n, n);
+            }
+            
+          })), eq, []);
+
+Test.run([
+      [
+        "ArrayTests.res",
+        52,
+        20,
+        30
+      ],
+      "keepSome"
+    ], Core__Array.keepSome([
+          1,
+          undefined,
+          3
+        ]), eq, [
+      1,
+      3
+    ]);
+
+Test.run([
+      [
+        "ArrayTests.res",
+        54,
+        13,
+        34
+      ],
+      "keepSome - all Some"
+    ], Core__Array.keepSome([
+          1,
+          2,
+          3
+        ]), eq, [
+      1,
+      2,
+      3
+    ]);
+
+Test.run([
+      [
+        "ArrayTests.res",
+        59,
+        20,
+        41
+      ],
+      "keepSome - all None"
+    ], Core__Array.keepSome([
+          undefined,
+          undefined,
+          undefined
+        ]), eq, []);
+
+Test.run([
+      [
+        "ArrayTests.res",
+        60,
+        20,
+        38
+      ],
+      "keepSome - empty"
+    ], Core__Array.keepSome([]), eq, []);
+
+Test.run([
+      [
+        "ArrayTests.res",
+        63,
+        13,
+        22
+      ],
+      "findMap"
+    ], Core__Array.findMap([
+          1,
+          2,
+          3,
+          4,
+          5,
+          6
+        ], (function (n) {
+            if (n % 2 === 0) {
+              return n - 8 | 0;
+            }
+            
+          })), eq, -6);
+
+Test.run([
+      [
+        "ArrayTests.res",
+        68,
+        20,
+        40
+      ],
+      "findMap - no match"
+    ], Core__Array.findMap([
+          1,
+          2,
+          3,
+          4,
+          5,
+          6
+        ], (function (param) {
+            
+          })), eq, undefined);
+
+Test.run([
+      [
+        "ArrayTests.res",
+        70,
+        13,
+        30
+      ],
+      "findMap - empty"
+    ], Core__Array.findMap([], (function (n) {
+            if (n % 2 === 0) {
+              return Math.imul(n, n);
+            }
+            
+          })), eq, undefined);
+
+export {
+  eq ,
+}
+/*  Not a pure module */
diff --git a/test/ArrayTests.res b/test/ArrayTests.res
new file mode 100644
index 00000000..7148fd08
--- /dev/null
+++ b/test/ArrayTests.res
@@ -0,0 +1,74 @@
+open RescriptCore
+
+let eq = (a, b) => a == b
+
+Test.run(__POS_OF__("make"), Array.make(~length=6, 7), eq, [7, 7, 7, 7, 7, 7])
+
+Test.run(
+  __POS_OF__("fromInitializer"),
+  Array.fromInitializer(~length=7, i => i + 3),
+  eq,
+  [3, 4, 5, 6, 7, 8, 9],
+)
+
+Test.run(__POS_OF__("reduce"), Array.reduce([1, 2, 3], list{}, List.add), eq, list{3, 2, 1})
+Test.run(__POS_OF__("reduce - empty"), Array.reduce([], list{}, List.add), eq, list{})
+
+Test.run(
+  __POS_OF__("reduceReverse"),
+  Array.reduceReverse([1, 2, 3], list{}, List.add),
+  eq,
+  list{1, 2, 3},
+)
+Test.run(__POS_OF__("reduceReverse - empty"), Array.reduceReverse([], list{}, List.add), eq, list{})
+
+Test.run(__POS_OF__("shuffle - length"), Array.shuffle([1, 2, 3])->Array.length, eq, 3)
+
+Test.run(
+  __POS_OF__("shuffleInPlace - length"),
+  {
+    let arr = [1, 2, 3]
+    Array.shuffleInPlace(arr)
+    arr->Array.length
+  },
+  eq,
+  3,
+)
+
+Test.run(
+  __POS_OF__("filterMap"),
+  Array.filterMap([1, 2, 3, 4, 5, 6], n => mod(n, 2) == 0 ? Some(n * n) : None),
+  eq,
+  [4, 16, 36],
+)
+Test.run(__POS_OF__("filterMap - no match"), Array.filterMap([1, 2, 3, 4, 5, 6], _ => None), eq, [])
+Test.run(
+  __POS_OF__("filterMap - empty"),
+  Array.filterMap([], n => mod(n, 2) == 0 ? Some(n * n) : None),
+  eq,
+  [],
+)
+
+Test.run(__POS_OF__("keepSome"), Array.keepSome([Some(1), None, Some(3)]), eq, [1, 3])
+Test.run(
+  __POS_OF__("keepSome - all Some"),
+  Array.keepSome([Some(1), Some(2), Some(3)]),
+  eq,
+  [1, 2, 3],
+)
+Test.run(__POS_OF__("keepSome - all None"), Array.keepSome([None, None, None]), eq, [])
+Test.run(__POS_OF__("keepSome - empty"), Array.keepSome([]), eq, [])
+
+Test.run(
+  __POS_OF__("findMap"),
+  Array.findMap([1, 2, 3, 4, 5, 6], n => mod(n, 2) == 0 ? Some(n - 8) : None),
+  eq,
+  Some(-6),
+)
+Test.run(__POS_OF__("findMap - no match"), Array.findMap([1, 2, 3, 4, 5, 6], _ => None), eq, None)
+Test.run(
+  __POS_OF__("findMap - empty"),
+  Array.findMap([], n => mod(n, 2) == 0 ? Some(n * n) : None),
+  eq,
+  None,
+)
diff --git a/test/TestSuite.mjs b/test/TestSuite.mjs
new file mode 100644
index 00000000..59a2f4e7
--- /dev/null
+++ b/test/TestSuite.mjs
@@ -0,0 +1,35 @@
+// Generated by ReScript, PLEASE EDIT WITH CARE
+
+import * as ArrayTests from "./ArrayTests.mjs";
+import * as PromiseTest from "./PromiseTest.mjs";
+
+var TestError = PromiseTest.TestError;
+
+var fail = PromiseTest.fail;
+
+var equal = PromiseTest.equal;
+
+var Creation = PromiseTest.Creation;
+
+var ThenChaining = PromiseTest.ThenChaining;
+
+var Rejection = PromiseTest.Rejection;
+
+var Catching = PromiseTest.Catching;
+
+var Concurrently = PromiseTest.Concurrently;
+
+var eq = ArrayTests.eq;
+
+export {
+  TestError ,
+  fail ,
+  equal ,
+  Creation ,
+  ThenChaining ,
+  Rejection ,
+  Catching ,
+  Concurrently ,
+  eq ,
+}
+/* ArrayTests Not a pure module */
diff --git a/test/TestSuite.res b/test/TestSuite.res
new file mode 100644
index 00000000..a376fea1
--- /dev/null
+++ b/test/TestSuite.res
@@ -0,0 +1,2 @@
+include PromiseTest
+include ArrayTests

From 0090ab63926ac236e26e2bdeeffff911b8e8997d Mon Sep 17 00:00:00 2001
From: glennsl <glenn@slotte.net>
Date: Sun, 26 Feb 2023 15:17:33 +0100
Subject: [PATCH 10/18] refactor(array): bind to native reduce instead of
 reimplementing it

---
 src/Core__Array.mjs  | 10 ----------
 src/Core__Array.res  | 10 +---------
 src/Core__Array.resi |  9 +++++----
 test/ArrayTests.mjs  | 12 ++++++------
 test/ArrayTests.res  |  4 ++--
 test/TempTests.mjs   |  9 ++++-----
 test/TempTests.res   |  2 +-
 7 files changed, 19 insertions(+), 37 deletions(-)

diff --git a/src/Core__Array.mjs b/src/Core__Array.mjs
index debbd163..63e7bbaf 100644
--- a/src/Core__Array.mjs
+++ b/src/Core__Array.mjs
@@ -46,15 +46,6 @@ function sort(arr, cmp) {
   return result;
 }
 
-function reduce(a, x, f) {
-  var f$1 = Curry.__2(f);
-  var r = x;
-  for(var i = 0 ,i_finish = a.length; i < i_finish; ++i){
-    r = f$1(r, a[i]);
-  }
-  return r;
-}
-
 function reduceWithIndex(a, x, f) {
   var f$1 = Curry.__3(f);
   var r = x;
@@ -155,7 +146,6 @@ export {
   sort ,
   indexOfOpt ,
   lastIndexOfOpt ,
-  reduce ,
   reduceReverse ,
   reduceWithIndex ,
   findIndexOpt ,
diff --git a/src/Core__Array.res b/src/Core__Array.res
index 77c3297d..188ea8fb 100644
--- a/src/Core__Array.res
+++ b/src/Core__Array.res
@@ -127,15 +127,7 @@ let sort = (arr, cmp) => {
 @send external map: (array<'a>, 'a => 'b) => array<'b> = "map"
 @send external mapWithIndex: (array<'a>, ('a, int) => 'b) => array<'b> = "map"
 
-let reduceU = (a, x, f) => {
-  let r = ref(x)
-  for i in 0 to length(a) - 1 {
-    r.contents = f(. r.contents, getUnsafe(a, i))
-  }
-  r.contents
-}
-
-let reduce = (a, x, f) => reduceU(a, x, (. a, b) => f(a, b))
+@send external reduce: (array<'b>, ('a, 'b) => 'a, 'a) => 'a = "reduce"
 
 let reduceWithIndexU = (a, x, f) => {
   let r = ref(x)
diff --git a/src/Core__Array.resi b/src/Core__Array.resi
index 11457d5f..f411b361 100644
--- a/src/Core__Array.resi
+++ b/src/Core__Array.resi
@@ -59,17 +59,18 @@ let lastIndexOfOpt: (array<'a>, 'a) => option<int>
 @send external mapWithIndex: (array<'a>, ('a, int) => 'b) => array<'b> = "map"
 
 /**
-  `reduce(xs, init, f)`
+  `reduce(xs, f, init)`
 
   Applies `f` to each element of `xs` from beginning to end. Function `f` has two parameters: the item from the list and an “accumulator”; which starts with a value of `init`. `reduce` returns the final value of the accumulator.
 
   ```res example
-  Array.reduce([2, 3, 4], 1, (a, b) => a + b) == 10
+  Array.reduce([2, 3, 4], (a, b) => a + b, 1) == 10
 
-  Array.reduce(["a", "b", "c", "d"], "", (a, b) => a ++ b) == "abcd"
+  Array.reduce(["a", "b", "c", "d"], (a, b) => a ++ b, "") == "abcd"
   ```
 */
-let reduce: (array<'b>, 'a, ('a, 'b) => 'a) => 'a
+@send
+external reduce: (array<'b>, ('a, 'b) => 'a, 'a) => 'a = "reduce"
 
 /**
   `reduceReverse(xs, init, f)`
diff --git a/test/ArrayTests.mjs b/test/ArrayTests.mjs
index bc52af57..0792d28c 100644
--- a/test/ArrayTests.mjs
+++ b/test/ArrayTests.mjs
@@ -52,11 +52,11 @@ Test.run([
         28
       ],
       "reduce"
-    ], Core__Array.reduce([
-          1,
-          2,
-          3
-        ], /* [] */0, Core__List.add), eq, {
+    ], [
+        1,
+        2,
+        3
+      ].reduce(Core__List.add, /* [] */0), eq, {
       hd: 3,
       tl: {
         hd: 2,
@@ -75,7 +75,7 @@ Test.run([
         36
       ],
       "reduce - empty"
-    ], Core__Array.reduce([], /* [] */0, Core__List.add), eq, /* [] */0);
+    ], [].reduce(Core__List.add, /* [] */0), eq, /* [] */0);
 
 Test.run([
       [
diff --git a/test/ArrayTests.res b/test/ArrayTests.res
index 7148fd08..ec08c4ea 100644
--- a/test/ArrayTests.res
+++ b/test/ArrayTests.res
@@ -11,8 +11,8 @@ Test.run(
   [3, 4, 5, 6, 7, 8, 9],
 )
 
-Test.run(__POS_OF__("reduce"), Array.reduce([1, 2, 3], list{}, List.add), eq, list{3, 2, 1})
-Test.run(__POS_OF__("reduce - empty"), Array.reduce([], list{}, List.add), eq, list{})
+Test.run(__POS_OF__("reduce"), Array.reduce([1, 2, 3], List.add, list{}), eq, list{3, 2, 1})
+Test.run(__POS_OF__("reduce - empty"), Array.reduce([], List.add, list{}), eq, list{})
 
 Test.run(
   __POS_OF__("reduceReverse"),
diff --git a/test/TempTests.mjs b/test/TempTests.mjs
index 9807a51a..cfd7146b 100644
--- a/test/TempTests.mjs
+++ b/test/TempTests.mjs
@@ -4,7 +4,6 @@ import * as Core__Int from "../src/Core__Int.mjs";
 import * as Core__Dict from "../src/Core__Dict.mjs";
 import * as Core__JSON from "../src/Core__JSON.mjs";
 import * as Caml_option from "rescript/lib/es6/caml_option.js";
-import * as Core__Array from "../src/Core__Array.mjs";
 import * as Core__Float from "../src/Core__Float.mjs";
 import * as Core__BigInt from "../src/Core__BigInt.mjs";
 import * as Core__Option from "../src/Core__Option.mjs";
@@ -22,11 +21,11 @@ var array = [
   4
 ];
 
-console.info(Core__Array.reduce(array.map(function (x) {
-              return (x << 1);
-            }), 0, (function (a, b) {
+console.info(array.map(function (x) {
+            return (x << 1);
+          }).reduce((function (a, b) {
             return a + b | 0;
-          })));
+          }), 0));
 
 console.info(typeof array);
 
diff --git a/test/TempTests.res b/test/TempTests.res
index 82784cea..9b7d5a6b 100644
--- a/test/TempTests.res
+++ b/test/TempTests.res
@@ -4,7 +4,7 @@ Console.info("")
 Console.info("Array")
 Console.info("---")
 let array = [1, 2, 3, 4]
-Console.info(array->Array.map(x => x * 2)->Array.reduce(0, (a, b) => a + b))
+Console.info(array->Array.map(x => x * 2)->Array.reduce((a, b) => a + b, 0))
 Console.info(typeof(array))
 
 Console.info("")

From a2e2df9f3d0ace63785f5a7bd029f7d19c7d66fd Mon Sep 17 00:00:00 2001
From: glennsl <glenn@slotte.net>
Date: Sun, 26 Feb 2023 15:21:08 +0100
Subject: [PATCH 11/18] refactor(array): replace reduceReverse with native
 binding to reduceRight

---
 src/Core__Array.mjs  | 10 ----------
 src/Core__Array.res  | 11 ++---------
 src/Core__Array.resi |  7 ++++---
 test/ArrayTests.mjs  | 20 ++++++++++----------
 test/ArrayTests.res  |  6 +++---
 5 files changed, 19 insertions(+), 35 deletions(-)

diff --git a/src/Core__Array.mjs b/src/Core__Array.mjs
index 63e7bbaf..446f0c72 100644
--- a/src/Core__Array.mjs
+++ b/src/Core__Array.mjs
@@ -55,15 +55,6 @@ function reduceWithIndex(a, x, f) {
   return r;
 }
 
-function reduceReverse(a, x, f) {
-  var f$1 = Curry.__2(f);
-  var r = x;
-  for(var i = a.length - 1 | 0; i >= 0; --i){
-    r = f$1(r, a[i]);
-  }
-  return r;
-}
-
 function findIndexOpt(array, finder) {
   var index = array.findIndex(finder);
   if (index !== -1) {
@@ -146,7 +137,6 @@ export {
   sort ,
   indexOfOpt ,
   lastIndexOfOpt ,
-  reduceReverse ,
   reduceWithIndex ,
   findIndexOpt ,
   reverse ,
diff --git a/src/Core__Array.res b/src/Core__Array.res
index 188ea8fb..aecb7d5d 100644
--- a/src/Core__Array.res
+++ b/src/Core__Array.res
@@ -139,15 +139,8 @@ let reduceWithIndexU = (a, x, f) => {
 
 let reduceWithIndex = (a, x, f) => reduceWithIndexU(a, x, (. a, b, c) => f(a, b, c))
 
-let reduceReverseU = (a, x, f) => {
-  let r = ref(x)
-  for i in length(a) - 1 downto 0 {
-    r.contents = f(. r.contents, getUnsafe(a, i))
-  }
-  r.contents
-}
-
-let reduceReverse = (a, x, f) => reduceReverseU(a, x, (. a, b) => f(a, b))
+@send
+external reduceRight: (array<'b>, ('a, 'b) => 'a, 'a) => 'a = "reduceRight"
 
 @send external some: (array<'a>, 'a => bool) => bool = "some"
 @send external someWithIndex: (array<'a>, ('a, int) => bool) => bool = "some"
diff --git a/src/Core__Array.resi b/src/Core__Array.resi
index f411b361..505997ae 100644
--- a/src/Core__Array.resi
+++ b/src/Core__Array.resi
@@ -73,15 +73,16 @@ let lastIndexOfOpt: (array<'a>, 'a) => option<int>
 external reduce: (array<'b>, ('a, 'b) => 'a, 'a) => 'a = "reduce"
 
 /**
-  `reduceReverse(xs, init, f)`
+  `reduceRight(xs, f, init)`
 
   Works like `Array.reduce`; except that function `f` is applied to each item of `xs` from the last back to the first.
 
   ```res example
-  Array.reduceReverse(["a", "b", "c", "d"], "", (a, b) => a ++ b) == "dcba"
+  Array.reduceRight(["a", "b", "c", "d"], (a, b) => a ++ b, "") == "dcba"
   ```
 */
-let reduceReverse: (array<'b>, 'a, ('a, 'b) => 'a) => 'a
+@send
+external reduceRight: (array<'b>, ('a, 'b) => 'a, 'a) => 'a = "reduceRight"
 
 /**
   Applies `f` to each element of `xs` from beginning to end. Function `f` has three parameters: the item from the array and an “accumulator”, which starts with a value of `init` and the index of each element. `reduceWithIndex` returns the final value of the accumulator.
diff --git a/test/ArrayTests.mjs b/test/ArrayTests.mjs
index 0792d28c..10c4c863 100644
--- a/test/ArrayTests.mjs
+++ b/test/ArrayTests.mjs
@@ -82,14 +82,14 @@ Test.run([
         "ArrayTests.res",
         18,
         13,
-        28
+        26
       ],
-      "reduceReverse"
-    ], Core__Array.reduceReverse([
-          1,
-          2,
-          3
-        ], /* [] */0, Core__List.add), eq, {
+      "reduceRight"
+    ], [
+        1,
+        2,
+        3
+      ].reduceRight(Core__List.add, /* [] */0), eq, {
       hd: 1,
       tl: {
         hd: 2,
@@ -105,10 +105,10 @@ Test.run([
         "ArrayTests.res",
         23,
         20,
-        43
+        41
       ],
-      "reduceReverse - empty"
-    ], Core__Array.reduceReverse([], /* [] */0, Core__List.add), eq, /* [] */0);
+      "reduceRight - empty"
+    ], [].reduceRight(Core__List.add, /* [] */0), eq, /* [] */0);
 
 Test.run([
       [
diff --git a/test/ArrayTests.res b/test/ArrayTests.res
index ec08c4ea..d5610803 100644
--- a/test/ArrayTests.res
+++ b/test/ArrayTests.res
@@ -15,12 +15,12 @@ Test.run(__POS_OF__("reduce"), Array.reduce([1, 2, 3], List.add, list{}), eq, li
 Test.run(__POS_OF__("reduce - empty"), Array.reduce([], List.add, list{}), eq, list{})
 
 Test.run(
-  __POS_OF__("reduceReverse"),
-  Array.reduceReverse([1, 2, 3], list{}, List.add),
+  __POS_OF__("reduceRight"),
+  Array.reduceRight([1, 2, 3], List.add, list{}),
   eq,
   list{1, 2, 3},
 )
-Test.run(__POS_OF__("reduceReverse - empty"), Array.reduceReverse([], list{}, List.add), eq, list{})
+Test.run(__POS_OF__("reduceRight - empty"), Array.reduceRight([], List.add, list{}), eq, list{})
 
 Test.run(__POS_OF__("shuffle - length"), Array.shuffle([1, 2, 3])->Array.length, eq, 3)
 

From 3042949160d207057f33ffa87ab236a6b44a15f6 Mon Sep 17 00:00:00 2001
From: glennsl <glenn@slotte.net>
Date: Sun, 26 Feb 2023 15:25:22 +0100
Subject: [PATCH 12/18] refactor(array): use native reduceWithIndex instead of
 reimplementing it

---
 src/Core__Array.mjs  | 10 -------
 src/Core__Array.res  | 12 +-------
 src/Core__Array.resi | 17 ++++++-----
 test/ArrayTests.mjs  | 69 +++++++++++++++++++++++++++++++++++---------
 test/ArrayTests.res  | 13 +++++++++
 5 files changed, 80 insertions(+), 41 deletions(-)

diff --git a/src/Core__Array.mjs b/src/Core__Array.mjs
index 446f0c72..a9fea805 100644
--- a/src/Core__Array.mjs
+++ b/src/Core__Array.mjs
@@ -46,15 +46,6 @@ function sort(arr, cmp) {
   return result;
 }
 
-function reduceWithIndex(a, x, f) {
-  var f$1 = Curry.__3(f);
-  var r = x;
-  for(var i = 0 ,i_finish = a.length; i < i_finish; ++i){
-    r = f$1(r, a[i], i);
-  }
-  return r;
-}
-
 function findIndexOpt(array, finder) {
   var index = array.findIndex(finder);
   if (index !== -1) {
@@ -137,7 +128,6 @@ export {
   sort ,
   indexOfOpt ,
   lastIndexOfOpt ,
-  reduceWithIndex ,
   findIndexOpt ,
   reverse ,
   filterMap ,
diff --git a/src/Core__Array.res b/src/Core__Array.res
index aecb7d5d..33b8188f 100644
--- a/src/Core__Array.res
+++ b/src/Core__Array.res
@@ -128,17 +128,7 @@ let sort = (arr, cmp) => {
 @send external mapWithIndex: (array<'a>, ('a, int) => 'b) => array<'b> = "map"
 
 @send external reduce: (array<'b>, ('a, 'b) => 'a, 'a) => 'a = "reduce"
-
-let reduceWithIndexU = (a, x, f) => {
-  let r = ref(x)
-  for i in 0 to length(a) - 1 {
-    r.contents = f(. r.contents, getUnsafe(a, i), i)
-  }
-  r.contents
-}
-
-let reduceWithIndex = (a, x, f) => reduceWithIndexU(a, x, (. a, b, c) => f(a, b, c))
-
+@send external reduceWithIndex: (array<'b>, ('a, 'b, int) => 'a, 'a) => 'a = "reduce"
 @send
 external reduceRight: (array<'b>, ('a, 'b) => 'a, 'a) => 'a = "reduceRight"
 
diff --git a/src/Core__Array.resi b/src/Core__Array.resi
index 505997ae..f01983cf 100644
--- a/src/Core__Array.resi
+++ b/src/Core__Array.resi
@@ -73,25 +73,28 @@ let lastIndexOfOpt: (array<'a>, 'a) => option<int>
 external reduce: (array<'b>, ('a, 'b) => 'a, 'a) => 'a = "reduce"
 
 /**
-  `reduceRight(xs, f, init)`
+  `reduceWithIndex(xs, f, init)`
 
-  Works like `Array.reduce`; except that function `f` is applied to each item of `xs` from the last back to the first.
+  Applies `f` to each element of `xs` from beginning to end. Function `f` has three parameters: the item from the array and an “accumulator”, which starts with a value of `init` and the index of each element. `reduceWithIndex` returns the final value of the accumulator.
 
   ```res example
-  Array.reduceRight(["a", "b", "c", "d"], (a, b) => a ++ b, "") == "dcba"
+  Array.reduceWithIndex([1, 2, 3, 4], (acc, x, i) => acc + x + i, 0) == 16
   ```
 */
 @send
-external reduceRight: (array<'b>, ('a, 'b) => 'a, 'a) => 'a = "reduceRight"
+external reduceWithIndex: (array<'b>, ('a, 'b, int) => 'a, 'a) => 'a = "reduce"
 
 /**
-  Applies `f` to each element of `xs` from beginning to end. Function `f` has three parameters: the item from the array and an “accumulator”, which starts with a value of `init` and the index of each element. `reduceWithIndex` returns the final value of the accumulator.
+  `reduceRight(xs, f, init)`
+
+  Works like `Array.reduce`; except that function `f` is applied to each item of `xs` from the last back to the first.
 
   ```res example
-  Array.reduceWithIndex([1, 2, 3, 4], 0, (acc, x, i) => acc + x + i) == 16
+  Array.reduceRight(["a", "b", "c", "d"], (a, b) => a ++ b, "") == "dcba"
   ```
 */
-let reduceWithIndex: (array<'a>, 'b, ('b, 'a, int) => 'b) => 'b
+@send
+external reduceRight: (array<'b>, ('a, 'b) => 'a, 'a) => 'a = "reduceRight"
 
 @send external some: (array<'a>, 'a => bool) => bool = "some"
 @send external someWithIndex: (array<'a>, ('a, int) => bool) => bool = "some"
diff --git a/test/ArrayTests.mjs b/test/ArrayTests.mjs
index 10c4c863..c4a01f5a 100644
--- a/test/ArrayTests.mjs
+++ b/test/ArrayTests.mjs
@@ -82,6 +82,49 @@ Test.run([
         "ArrayTests.res",
         18,
         13,
+        30
+      ],
+      "reduceWithIndex"
+    ], [
+        1,
+        2,
+        3
+      ].reduce((function (acc, v, i) {
+            return {
+                    hd: v + i | 0,
+                    tl: acc
+                  };
+          }), /* [] */0), eq, {
+      hd: 5,
+      tl: {
+        hd: 3,
+        tl: {
+          hd: 1,
+          tl: /* [] */0
+        }
+      }
+    });
+
+Test.run([
+      [
+        "ArrayTests.res",
+        24,
+        13,
+        38
+      ],
+      "reduceWithIndex - empty"
+    ], [].reduce((function (acc, v, i) {
+            return {
+                    hd: v + i | 0,
+                    tl: acc
+                  };
+          }), /* [] */0), eq, /* [] */0);
+
+Test.run([
+      [
+        "ArrayTests.res",
+        31,
+        13,
         26
       ],
       "reduceRight"
@@ -103,7 +146,7 @@ Test.run([
 Test.run([
       [
         "ArrayTests.res",
-        23,
+        36,
         20,
         41
       ],
@@ -113,7 +156,7 @@ Test.run([
 Test.run([
       [
         "ArrayTests.res",
-        25,
+        38,
         20,
         38
       ],
@@ -133,7 +176,7 @@ var arr = [
 Test.run([
       [
         "ArrayTests.res",
-        28,
+        41,
         13,
         38
       ],
@@ -143,7 +186,7 @@ Test.run([
 Test.run([
       [
         "ArrayTests.res",
-        39,
+        52,
         13,
         24
       ],
@@ -169,7 +212,7 @@ Test.run([
 Test.run([
       [
         "ArrayTests.res",
-        44,
+        57,
         20,
         42
       ],
@@ -188,7 +231,7 @@ Test.run([
 Test.run([
       [
         "ArrayTests.res",
-        46,
+        59,
         13,
         32
       ],
@@ -203,7 +246,7 @@ Test.run([
 Test.run([
       [
         "ArrayTests.res",
-        52,
+        65,
         20,
         30
       ],
@@ -220,7 +263,7 @@ Test.run([
 Test.run([
       [
         "ArrayTests.res",
-        54,
+        67,
         13,
         34
       ],
@@ -238,7 +281,7 @@ Test.run([
 Test.run([
       [
         "ArrayTests.res",
-        59,
+        72,
         20,
         41
       ],
@@ -252,7 +295,7 @@ Test.run([
 Test.run([
       [
         "ArrayTests.res",
-        60,
+        73,
         20,
         38
       ],
@@ -262,7 +305,7 @@ Test.run([
 Test.run([
       [
         "ArrayTests.res",
-        63,
+        76,
         13,
         22
       ],
@@ -284,7 +327,7 @@ Test.run([
 Test.run([
       [
         "ArrayTests.res",
-        68,
+        81,
         20,
         40
       ],
@@ -303,7 +346,7 @@ Test.run([
 Test.run([
       [
         "ArrayTests.res",
-        70,
+        83,
         13,
         30
       ],
diff --git a/test/ArrayTests.res b/test/ArrayTests.res
index d5610803..0042e658 100644
--- a/test/ArrayTests.res
+++ b/test/ArrayTests.res
@@ -14,6 +14,19 @@ Test.run(
 Test.run(__POS_OF__("reduce"), Array.reduce([1, 2, 3], List.add, list{}), eq, list{3, 2, 1})
 Test.run(__POS_OF__("reduce - empty"), Array.reduce([], List.add, list{}), eq, list{})
 
+Test.run(
+  __POS_OF__("reduceWithIndex"),
+  Array.reduceWithIndex([1, 2, 3], (acc, v, i) => list{v + i, ...acc}, list{}),
+  eq,
+  list{5, 3, 1},
+)
+Test.run(
+  __POS_OF__("reduceWithIndex - empty"),
+  Array.reduceWithIndex([], (acc, v, i) => list{v + i, ...acc}, list{}),
+  eq,
+  list{},
+)
+
 Test.run(
   __POS_OF__("reduceRight"),
   Array.reduceRight([1, 2, 3], List.add, list{}),

From 8eb7433cc2548bed0a575efb7f9c6deaaf148b46 Mon Sep 17 00:00:00 2001
From: glennsl <glenn@slotte.net>
Date: Sun, 26 Feb 2023 15:31:39 +0100
Subject: [PATCH 13/18] feat(array): add reduceRightWithIndex

---
 src/Core__Array.res  |  2 ++
 src/Core__Array.resi | 12 ++++++++
 test/ArrayTests.mjs  | 67 ++++++++++++++++++++++++++++++++++++--------
 test/ArrayTests.res  | 13 +++++++++
 4 files changed, 82 insertions(+), 12 deletions(-)

diff --git a/src/Core__Array.res b/src/Core__Array.res
index 33b8188f..b47b4b32 100644
--- a/src/Core__Array.res
+++ b/src/Core__Array.res
@@ -131,6 +131,8 @@ let sort = (arr, cmp) => {
 @send external reduceWithIndex: (array<'b>, ('a, 'b, int) => 'a, 'a) => 'a = "reduce"
 @send
 external reduceRight: (array<'b>, ('a, 'b) => 'a, 'a) => 'a = "reduceRight"
+@send
+external reduceRightWithIndex: (array<'b>, ('a, 'b, int) => 'a, 'a) => 'a = "reduceRight"
 
 @send external some: (array<'a>, 'a => bool) => bool = "some"
 @send external someWithIndex: (array<'a>, ('a, int) => bool) => bool = "some"
diff --git a/src/Core__Array.resi b/src/Core__Array.resi
index f01983cf..f49e7e92 100644
--- a/src/Core__Array.resi
+++ b/src/Core__Array.resi
@@ -96,6 +96,18 @@ external reduceWithIndex: (array<'b>, ('a, 'b, int) => 'a, 'a) => 'a = "reduce"
 @send
 external reduceRight: (array<'b>, ('a, 'b) => 'a, 'a) => 'a = "reduceRight"
 
+/**
+  `reduceRightWithIndex(xs, f, init)`
+
+  Like `reduceRight`, but with an additional index argument on the callback function.
+
+  ```res example
+  Array.reduceRightWithIndex([1, 2, 3, 4], (acc, x, i) => acc + x + i, 0) == 16
+  ```
+*/
+@send
+external reduceRightWithIndex: (array<'b>, ('a, 'b, int) => 'a, 'a) => 'a = "reduceRight"
+
 @send external some: (array<'a>, 'a => bool) => bool = "some"
 @send external someWithIndex: (array<'a>, ('a, int) => bool) => bool = "some"
 @get_index external get: (array<'a>, int) => option<'a> = ""
diff --git a/test/ArrayTests.mjs b/test/ArrayTests.mjs
index c4a01f5a..9f8de3dd 100644
--- a/test/ArrayTests.mjs
+++ b/test/ArrayTests.mjs
@@ -156,7 +156,50 @@ Test.run([
 Test.run([
       [
         "ArrayTests.res",
-        38,
+        39,
+        13,
+        35
+      ],
+      "reduceEightWithIndex"
+    ], [
+        1,
+        2,
+        3
+      ].reduceRight((function (acc, v, i) {
+            return {
+                    hd: v + i | 0,
+                    tl: acc
+                  };
+          }), /* [] */0), eq, {
+      hd: 1,
+      tl: {
+        hd: 3,
+        tl: {
+          hd: 5,
+          tl: /* [] */0
+        }
+      }
+    });
+
+Test.run([
+      [
+        "ArrayTests.res",
+        45,
+        13,
+        38
+      ],
+      "reduceWithIndex - empty"
+    ], [].reduceRight((function (acc, v, i) {
+            return {
+                    hd: v + i | 0,
+                    tl: acc
+                  };
+          }), /* [] */0), eq, /* [] */0);
+
+Test.run([
+      [
+        "ArrayTests.res",
+        51,
         20,
         38
       ],
@@ -176,7 +219,7 @@ var arr = [
 Test.run([
       [
         "ArrayTests.res",
-        41,
+        54,
         13,
         38
       ],
@@ -186,7 +229,7 @@ Test.run([
 Test.run([
       [
         "ArrayTests.res",
-        52,
+        65,
         13,
         24
       ],
@@ -212,7 +255,7 @@ Test.run([
 Test.run([
       [
         "ArrayTests.res",
-        57,
+        70,
         20,
         42
       ],
@@ -231,7 +274,7 @@ Test.run([
 Test.run([
       [
         "ArrayTests.res",
-        59,
+        72,
         13,
         32
       ],
@@ -246,7 +289,7 @@ Test.run([
 Test.run([
       [
         "ArrayTests.res",
-        65,
+        78,
         20,
         30
       ],
@@ -263,7 +306,7 @@ Test.run([
 Test.run([
       [
         "ArrayTests.res",
-        67,
+        80,
         13,
         34
       ],
@@ -281,7 +324,7 @@ Test.run([
 Test.run([
       [
         "ArrayTests.res",
-        72,
+        85,
         20,
         41
       ],
@@ -295,7 +338,7 @@ Test.run([
 Test.run([
       [
         "ArrayTests.res",
-        73,
+        86,
         20,
         38
       ],
@@ -305,7 +348,7 @@ Test.run([
 Test.run([
       [
         "ArrayTests.res",
-        76,
+        89,
         13,
         22
       ],
@@ -327,7 +370,7 @@ Test.run([
 Test.run([
       [
         "ArrayTests.res",
-        81,
+        94,
         20,
         40
       ],
@@ -346,7 +389,7 @@ Test.run([
 Test.run([
       [
         "ArrayTests.res",
-        83,
+        96,
         13,
         30
       ],
diff --git a/test/ArrayTests.res b/test/ArrayTests.res
index 0042e658..74351ed4 100644
--- a/test/ArrayTests.res
+++ b/test/ArrayTests.res
@@ -35,6 +35,19 @@ Test.run(
 )
 Test.run(__POS_OF__("reduceRight - empty"), Array.reduceRight([], List.add, list{}), eq, list{})
 
+Test.run(
+  __POS_OF__("reduceEightWithIndex"),
+  Array.reduceRightWithIndex([1, 2, 3], (acc, v, i) => list{v + i, ...acc}, list{}),
+  eq,
+  list{1, 3, 5},
+)
+Test.run(
+  __POS_OF__("reduceWithIndex - empty"),
+  Array.reduceRightWithIndex([], (acc, v, i) => list{v + i, ...acc}, list{}),
+  eq,
+  list{},
+)
+
 Test.run(__POS_OF__("shuffle - length"), Array.shuffle([1, 2, 3])->Array.length, eq, 3)
 
 Test.run(

From b2f539ec8fce29b678cede3cb89e641e3d69837d Mon Sep 17 00:00:00 2001
From: glennsl <glenn@slotte.net>
Date: Sun, 26 Feb 2023 15:52:27 +0100
Subject: [PATCH 14/18] docs(array): add docs for make, fromInitializer,
 findMap and keepSome

---
 src/Core__Array.resi | 42 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 42 insertions(+)

diff --git a/src/Core__Array.resi b/src/Core__Array.resi
index f49e7e92..ef574c26 100644
--- a/src/Core__Array.resi
+++ b/src/Core__Array.resi
@@ -5,8 +5,29 @@
 external fromArrayLikeWithMap: (Js.Array2.array_like<'a>, 'a => 'b) => array<'b> = "Array.from"
 @val external fromIterator: Core__Iterator.t<'a> => array<'a> = "Array.from"
 @val external fromIteratorWithMap: (Core__Iterator.t<'a>, 'a => 'b) => array<'b> = "Array.from"
+
+/**
+  `make(~length, init)`
+
+  Creates an array of length `length` initialized with the value of `init`.
+
+  ```res example
+  Array.make(~length=3, #apple) == [#apple, #apple, #apple]
+  ```
+*/
 let make: (~length: int, 'a) => array<'a>
+
+/**
+  `fromInitializer(~length, f)`
+
+  Creates an array of length `length` initialized with the value returned from `f ` for each index.
+
+  ```res example
+  Array.make(~length=3, i => i + 3) == [3, 4, 5]
+  ```
+*/
 let fromInitializer: (~length: int, int => 'a) => array<'a>
+
 @val external isArray: 'a => bool = "Array.isArray"
 @get external length: array<'a> => int = "length"
 @send external copyAllWithin: (array<'a>, ~target: int) => array<'a> = "copyWithin"
@@ -120,10 +141,31 @@ external setUnsafe: (array<'a>, int, 'a) => unit = "%array_unsafe_set"
 let findIndexOpt: (array<'a>, 'a => bool) => option<int>
 let reverse: array<'a> => array<'a>
 let filterMap: (array<'a>, 'a => option<'b>) => array<'b>
+
+/**
+  `fromInitializer(~length, f)`
+
+  Creates an array of length `length` initialized with the value returned from `f ` for each index.
+
+  ```res example
+  Array.make(~length=3, i => i + 3) == [3, 4, 5]
+  ```
+*/
 let keepSome: array<option<'a>> => array<'a>
 let shuffle: array<'a> => array<'a>
 let shuffleInPlace: array<'a> => unit
 @send external flatMap: (array<'a>, 'a => array<'b>) => array<'b> = "flatMap"
+
+/**
+  `findMap(arr, f)`
+
+  Calls `f` for each element and returns the first value from `f` that is `Some(_)`.
+  Otherwise returns `None`
+
+  ```res example
+  Array.findMap([1, 2, 3], n => mod(n, 2) ? Some(n - 2) : None) == 0
+  ```
+*/
 let findMap: (array<'a>, 'a => option<'b>) => option<'b>
 
 /**

From ffc18ee9ab8bdc284836824b04eb503da08c16fa Mon Sep 17 00:00:00 2001
From: glennsl <glenn@slotte.net>
Date: Sun, 26 Feb 2023 15:52:58 +0100
Subject: [PATCH 15/18] docs(changelog): update changelog for array additions

---
 CHANGELOG.md | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 8b5fe554..258cc59a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -18,6 +18,9 @@
 - Change `Float.fromString` signature. Now accepts only string. https://github.com/rescript-association/rescript-core/pull/54
 - Change `Float.parseFloat` signature. Now accepts only string. https://github.com/rescript-association/rescript-core/pull/54
 - Add `getExn`, `getUnsafe`, `getWithDefault`, `map`, `mapWithDefault` and `flatMap` to `Nullable`. https://github.com/rescript-association/rescript-core/pull/67
+- Add `make`, `fromInitializer`, `findMap`, `keepSome`, `reduceRight` and `reduceRightWithIndex`. https://github.com/rescript-association/rescript-core/pull/49
+- Remove `reduceReverse` in favor of `reduceRight`. https://github.com/rescript-association/rescript-core/pull/49
+- Fixed type signatures of `reduce` and `reduceWithIndex`. https://github.com/rescript-association/rescript-core/pull/49
 
 ### Documentation
 

From b80a80f10b4c925d6f91fe06c7493a876efc64a8 Mon Sep 17 00:00:00 2001
From: glennsl <glenn@slotte.net>
Date: Tue, 28 Feb 2023 20:02:08 +0100
Subject: [PATCH 16/18] docs(array): fix docstring fro keepSome

---
 src/Core__Array.resi | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/src/Core__Array.resi b/src/Core__Array.resi
index ef574c26..6efdda99 100644
--- a/src/Core__Array.resi
+++ b/src/Core__Array.resi
@@ -143,12 +143,13 @@ let reverse: array<'a> => array<'a>
 let filterMap: (array<'a>, 'a => option<'b>) => array<'b>
 
 /**
-  `fromInitializer(~length, f)`
+  `keepSome(arr)`
 
-  Creates an array of length `length` initialized with the value returned from `f ` for each index.
+  Returns a new array containing `value` for all elements that are `Some(value)`
+  and ignoring every value that is `None`
 
   ```res example
-  Array.make(~length=3, i => i + 3) == [3, 4, 5]
+  Array.keepSome([Some(1), None, Some(3)]) == [1, 3]
   ```
 */
 let keepSome: array<option<'a>> => array<'a>

From 6d4f25641fbdedfacfaedc6ab5008b6618fdc644 Mon Sep 17 00:00:00 2001
From: glennsl <glenn@slotte.net>
Date: Tue, 28 Feb 2023 20:06:32 +0100
Subject: [PATCH 17/18] fix(array): reorder args of reduce functions for better
 te inference

---
 src/Core__Array.mjs  | 20 ++++++++++++++++
 src/Core__Array.res  |  4 ++++
 src/Core__Array.resi | 12 ++++------
 test/ArrayTests.mjs  | 56 ++++++++++++++++++++++----------------------
 test/ArrayTests.res  | 16 ++++++-------
 test/TempTests.mjs   |  9 +++----
 test/TempTests.res   |  2 +-
 7 files changed, 70 insertions(+), 49 deletions(-)

diff --git a/src/Core__Array.mjs b/src/Core__Array.mjs
index a9fea805..1560df8f 100644
--- a/src/Core__Array.mjs
+++ b/src/Core__Array.mjs
@@ -46,6 +46,22 @@ function sort(arr, cmp) {
   return result;
 }
 
+function reduce(arr, init, f) {
+  return arr.reduce(f, init);
+}
+
+function reduceWithIndex(arr, init, f) {
+  return arr.reduce(f, init);
+}
+
+function reduceRight(arr, init, f) {
+  return arr.reduceRight(f, init);
+}
+
+function reduceRightWithIndex(arr, init, f) {
+  return arr.reduceRight(f, init);
+}
+
 function findIndexOpt(array, finder) {
   var index = array.findIndex(finder);
   if (index !== -1) {
@@ -128,6 +144,10 @@ export {
   sort ,
   indexOfOpt ,
   lastIndexOfOpt ,
+  reduce ,
+  reduceWithIndex ,
+  reduceRight ,
+  reduceRightWithIndex ,
   findIndexOpt ,
   reverse ,
   filterMap ,
diff --git a/src/Core__Array.res b/src/Core__Array.res
index b47b4b32..a1c2e853 100644
--- a/src/Core__Array.res
+++ b/src/Core__Array.res
@@ -128,11 +128,15 @@ let sort = (arr, cmp) => {
 @send external mapWithIndex: (array<'a>, ('a, int) => 'b) => array<'b> = "map"
 
 @send external reduce: (array<'b>, ('a, 'b) => 'a, 'a) => 'a = "reduce"
+let reduce = (arr, init, f) => reduce(arr, f, init)
 @send external reduceWithIndex: (array<'b>, ('a, 'b, int) => 'a, 'a) => 'a = "reduce"
+let reduceWithIndex = (arr, init, f) => reduceWithIndex(arr, f, init)
 @send
 external reduceRight: (array<'b>, ('a, 'b) => 'a, 'a) => 'a = "reduceRight"
+let reduceRight = (arr, init, f) => reduceRight(arr, f, init)
 @send
 external reduceRightWithIndex: (array<'b>, ('a, 'b, int) => 'a, 'a) => 'a = "reduceRight"
+let reduceRightWithIndex = (arr, init, f) => reduceRightWithIndex(arr, f, init)
 
 @send external some: (array<'a>, 'a => bool) => bool = "some"
 @send external someWithIndex: (array<'a>, ('a, int) => bool) => bool = "some"
diff --git a/src/Core__Array.resi b/src/Core__Array.resi
index 6efdda99..59329856 100644
--- a/src/Core__Array.resi
+++ b/src/Core__Array.resi
@@ -90,8 +90,7 @@ let lastIndexOfOpt: (array<'a>, 'a) => option<int>
   Array.reduce(["a", "b", "c", "d"], (a, b) => a ++ b, "") == "abcd"
   ```
 */
-@send
-external reduce: (array<'b>, ('a, 'b) => 'a, 'a) => 'a = "reduce"
+let reduce: (array<'b>, 'a, ('a, 'b) => 'a) => 'a
 
 /**
   `reduceWithIndex(xs, f, init)`
@@ -102,8 +101,7 @@ external reduce: (array<'b>, ('a, 'b) => 'a, 'a) => 'a = "reduce"
   Array.reduceWithIndex([1, 2, 3, 4], (acc, x, i) => acc + x + i, 0) == 16
   ```
 */
-@send
-external reduceWithIndex: (array<'b>, ('a, 'b, int) => 'a, 'a) => 'a = "reduce"
+let reduceWithIndex: (array<'b>, 'a, ('a, 'b, int) => 'a) => 'a
 
 /**
   `reduceRight(xs, f, init)`
@@ -114,8 +112,7 @@ external reduceWithIndex: (array<'b>, ('a, 'b, int) => 'a, 'a) => 'a = "reduce"
   Array.reduceRight(["a", "b", "c", "d"], (a, b) => a ++ b, "") == "dcba"
   ```
 */
-@send
-external reduceRight: (array<'b>, ('a, 'b) => 'a, 'a) => 'a = "reduceRight"
+let reduceRight: (array<'b>, 'a, ('a, 'b) => 'a) => 'a
 
 /**
   `reduceRightWithIndex(xs, f, init)`
@@ -126,8 +123,7 @@ external reduceRight: (array<'b>, ('a, 'b) => 'a, 'a) => 'a = "reduceRight"
   Array.reduceRightWithIndex([1, 2, 3, 4], (acc, x, i) => acc + x + i, 0) == 16
   ```
 */
-@send
-external reduceRightWithIndex: (array<'b>, ('a, 'b, int) => 'a, 'a) => 'a = "reduceRight"
+let reduceRightWithIndex: (array<'b>, 'a, ('a, 'b, int) => 'a) => 'a
 
 @send external some: (array<'a>, 'a => bool) => bool = "some"
 @send external someWithIndex: (array<'a>, ('a, int) => bool) => bool = "some"
diff --git a/test/ArrayTests.mjs b/test/ArrayTests.mjs
index 9f8de3dd..7cc4a4c6 100644
--- a/test/ArrayTests.mjs
+++ b/test/ArrayTests.mjs
@@ -52,11 +52,11 @@ Test.run([
         28
       ],
       "reduce"
-    ], [
-        1,
-        2,
-        3
-      ].reduce(Core__List.add, /* [] */0), eq, {
+    ], Core__Array.reduce([
+          1,
+          2,
+          3
+        ], /* [] */0, Core__List.add), eq, {
       hd: 3,
       tl: {
         hd: 2,
@@ -75,7 +75,7 @@ Test.run([
         36
       ],
       "reduce - empty"
-    ], [].reduce(Core__List.add, /* [] */0), eq, /* [] */0);
+    ], Core__Array.reduce([], /* [] */0, Core__List.add), eq, /* [] */0);
 
 Test.run([
       [
@@ -85,16 +85,16 @@ Test.run([
         30
       ],
       "reduceWithIndex"
-    ], [
-        1,
-        2,
-        3
-      ].reduce((function (acc, v, i) {
+    ], Core__Array.reduceWithIndex([
+          1,
+          2,
+          3
+        ], /* [] */0, (function (acc, v, i) {
             return {
                     hd: v + i | 0,
                     tl: acc
                   };
-          }), /* [] */0), eq, {
+          })), eq, {
       hd: 5,
       tl: {
         hd: 3,
@@ -113,12 +113,12 @@ Test.run([
         38
       ],
       "reduceWithIndex - empty"
-    ], [].reduce((function (acc, v, i) {
+    ], Core__Array.reduceWithIndex([], /* [] */0, (function (acc, v, i) {
             return {
                     hd: v + i | 0,
                     tl: acc
                   };
-          }), /* [] */0), eq, /* [] */0);
+          })), eq, /* [] */0);
 
 Test.run([
       [
@@ -128,11 +128,11 @@ Test.run([
         26
       ],
       "reduceRight"
-    ], [
-        1,
-        2,
-        3
-      ].reduceRight(Core__List.add, /* [] */0), eq, {
+    ], Core__Array.reduceRight([
+          1,
+          2,
+          3
+        ], /* [] */0, Core__List.add), eq, {
       hd: 1,
       tl: {
         hd: 2,
@@ -151,7 +151,7 @@ Test.run([
         41
       ],
       "reduceRight - empty"
-    ], [].reduceRight(Core__List.add, /* [] */0), eq, /* [] */0);
+    ], Core__Array.reduceRight([], /* [] */0, Core__List.add), eq, /* [] */0);
 
 Test.run([
       [
@@ -161,16 +161,16 @@ Test.run([
         35
       ],
       "reduceEightWithIndex"
-    ], [
-        1,
-        2,
-        3
-      ].reduceRight((function (acc, v, i) {
+    ], Core__Array.reduceRightWithIndex([
+          1,
+          2,
+          3
+        ], /* [] */0, (function (acc, v, i) {
             return {
                     hd: v + i | 0,
                     tl: acc
                   };
-          }), /* [] */0), eq, {
+          })), eq, {
       hd: 1,
       tl: {
         hd: 3,
@@ -189,12 +189,12 @@ Test.run([
         38
       ],
       "reduceWithIndex - empty"
-    ], [].reduceRight((function (acc, v, i) {
+    ], Core__Array.reduceRightWithIndex([], /* [] */0, (function (acc, v, i) {
             return {
                     hd: v + i | 0,
                     tl: acc
                   };
-          }), /* [] */0), eq, /* [] */0);
+          })), eq, /* [] */0);
 
 Test.run([
       [
diff --git a/test/ArrayTests.res b/test/ArrayTests.res
index 74351ed4..40c352f7 100644
--- a/test/ArrayTests.res
+++ b/test/ArrayTests.res
@@ -11,39 +11,39 @@ Test.run(
   [3, 4, 5, 6, 7, 8, 9],
 )
 
-Test.run(__POS_OF__("reduce"), Array.reduce([1, 2, 3], List.add, list{}), eq, list{3, 2, 1})
-Test.run(__POS_OF__("reduce - empty"), Array.reduce([], List.add, list{}), eq, list{})
+Test.run(__POS_OF__("reduce"), Array.reduce([1, 2, 3], list{}, List.add), eq, list{3, 2, 1})
+Test.run(__POS_OF__("reduce - empty"), Array.reduce([], list{}, List.add), eq, list{})
 
 Test.run(
   __POS_OF__("reduceWithIndex"),
-  Array.reduceWithIndex([1, 2, 3], (acc, v, i) => list{v + i, ...acc}, list{}),
+  Array.reduceWithIndex([1, 2, 3], list{}, (acc, v, i) => list{v + i, ...acc}),
   eq,
   list{5, 3, 1},
 )
 Test.run(
   __POS_OF__("reduceWithIndex - empty"),
-  Array.reduceWithIndex([], (acc, v, i) => list{v + i, ...acc}, list{}),
+  Array.reduceWithIndex([], list{}, (acc, v, i) => list{v + i, ...acc}),
   eq,
   list{},
 )
 
 Test.run(
   __POS_OF__("reduceRight"),
-  Array.reduceRight([1, 2, 3], List.add, list{}),
+  Array.reduceRight([1, 2, 3], list{}, List.add),
   eq,
   list{1, 2, 3},
 )
-Test.run(__POS_OF__("reduceRight - empty"), Array.reduceRight([], List.add, list{}), eq, list{})
+Test.run(__POS_OF__("reduceRight - empty"), Array.reduceRight([], list{}, List.add), eq, list{})
 
 Test.run(
   __POS_OF__("reduceEightWithIndex"),
-  Array.reduceRightWithIndex([1, 2, 3], (acc, v, i) => list{v + i, ...acc}, list{}),
+  Array.reduceRightWithIndex([1, 2, 3], list{}, (acc, v, i) => list{v + i, ...acc}),
   eq,
   list{1, 3, 5},
 )
 Test.run(
   __POS_OF__("reduceWithIndex - empty"),
-  Array.reduceRightWithIndex([], (acc, v, i) => list{v + i, ...acc}, list{}),
+  Array.reduceRightWithIndex([], list{}, (acc, v, i) => list{v + i, ...acc}),
   eq,
   list{},
 )
diff --git a/test/TempTests.mjs b/test/TempTests.mjs
index cfd7146b..9807a51a 100644
--- a/test/TempTests.mjs
+++ b/test/TempTests.mjs
@@ -4,6 +4,7 @@ import * as Core__Int from "../src/Core__Int.mjs";
 import * as Core__Dict from "../src/Core__Dict.mjs";
 import * as Core__JSON from "../src/Core__JSON.mjs";
 import * as Caml_option from "rescript/lib/es6/caml_option.js";
+import * as Core__Array from "../src/Core__Array.mjs";
 import * as Core__Float from "../src/Core__Float.mjs";
 import * as Core__BigInt from "../src/Core__BigInt.mjs";
 import * as Core__Option from "../src/Core__Option.mjs";
@@ -21,11 +22,11 @@ var array = [
   4
 ];
 
-console.info(array.map(function (x) {
-            return (x << 1);
-          }).reduce((function (a, b) {
+console.info(Core__Array.reduce(array.map(function (x) {
+              return (x << 1);
+            }), 0, (function (a, b) {
             return a + b | 0;
-          }), 0));
+          })));
 
 console.info(typeof array);
 
diff --git a/test/TempTests.res b/test/TempTests.res
index 9b7d5a6b..82784cea 100644
--- a/test/TempTests.res
+++ b/test/TempTests.res
@@ -4,7 +4,7 @@ Console.info("")
 Console.info("Array")
 Console.info("---")
 let array = [1, 2, 3, 4]
-Console.info(array->Array.map(x => x * 2)->Array.reduce((a, b) => a + b, 0))
+Console.info(array->Array.map(x => x * 2)->Array.reduce(0, (a, b) => a + b))
 Console.info(typeof(array))
 
 Console.info("")

From 616279f25b4005f6756f086985e801b51d9b4f70 Mon Sep 17 00:00:00 2001
From: glennsl <glenn@slotte.net>
Date: Tue, 28 Feb 2023 20:08:51 +0100
Subject: [PATCH 18/18] refactor(array): consistent type variable naming in
 reduce functions

---
 src/Core__Array.resi | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/Core__Array.resi b/src/Core__Array.resi
index 59329856..0bbb3984 100644
--- a/src/Core__Array.resi
+++ b/src/Core__Array.resi
@@ -90,7 +90,7 @@ let lastIndexOfOpt: (array<'a>, 'a) => option<int>
   Array.reduce(["a", "b", "c", "d"], (a, b) => a ++ b, "") == "abcd"
   ```
 */
-let reduce: (array<'b>, 'a, ('a, 'b) => 'a) => 'a
+let reduce: (array<'a>, 'b, ('b, 'a) => 'b) => 'b
 
 /**
   `reduceWithIndex(xs, f, init)`
@@ -101,7 +101,7 @@ let reduce: (array<'b>, 'a, ('a, 'b) => 'a) => 'a
   Array.reduceWithIndex([1, 2, 3, 4], (acc, x, i) => acc + x + i, 0) == 16
   ```
 */
-let reduceWithIndex: (array<'b>, 'a, ('a, 'b, int) => 'a) => 'a
+let reduceWithIndex: (array<'a>, 'b, ('b, 'a, int) => 'b) => 'b
 
 /**
   `reduceRight(xs, f, init)`
@@ -112,7 +112,7 @@ let reduceWithIndex: (array<'b>, 'a, ('a, 'b, int) => 'a) => 'a
   Array.reduceRight(["a", "b", "c", "d"], (a, b) => a ++ b, "") == "dcba"
   ```
 */
-let reduceRight: (array<'b>, 'a, ('a, 'b) => 'a) => 'a
+let reduceRight: (array<'a>, 'b, ('b, 'a) => 'b) => 'b
 
 /**
   `reduceRightWithIndex(xs, f, init)`
@@ -123,7 +123,7 @@ let reduceRight: (array<'b>, 'a, ('a, 'b) => 'a) => 'a
   Array.reduceRightWithIndex([1, 2, 3, 4], (acc, x, i) => acc + x + i, 0) == 16
   ```
 */
-let reduceRightWithIndex: (array<'b>, 'a, ('a, 'b, int) => 'a) => 'a
+let reduceRightWithIndex: (array<'a>, 'b, ('b, 'a, int) => 'b) => 'b
 
 @send external some: (array<'a>, 'a => bool) => bool = "some"
 @send external someWithIndex: (array<'a>, ('a, int) => bool) => bool = "some"