feat(array): add keepSome

Author: glennsl

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 ,

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))
 

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>