feat(int) add clamp

Author: glennsl

src/Core__Int.mjs

@@ -1,6 +1,8 @@
 // Generated by ReScript, PLEASE EDIT WITH CARE
 
+import * as Caml_obj from "rescript/lib/es6/caml_obj.js";
 import * as Pervasives from "rescript/lib/es6/pervasives.js";
+import * as Caml_option from "rescript/lib/es6/caml_option.js";
 import * as Core__Array from "./Core__Array.mjs";
 
 function equal(a, b) {
@@ -61,6 +63,25 @@ function range(start, end) {
   return rangeWithOptions(start, end, {});
 }
 
+function clamp(min, max, value) {
+  var value$1;
+  if (max !== undefined) {
+    var max$1 = Caml_option.valFromOption(max);
+    value$1 = Caml_obj.lessthan(max$1, value) ? max$1 : value;
+  } else {
+    value$1 = value;
+  }
+  if (min === undefined) {
+    return value$1;
+  }
+  var min$1 = Caml_option.valFromOption(min);
+  if (Caml_obj.greaterthan(min$1, value$1)) {
+    return min$1;
+  } else {
+    return value$1;
+  }
+}
+
 var Constants = {
   minValue: -2147483648,
   maxValue: 2147483647
@@ -73,5 +94,6 @@ export {
   fromString ,
   range ,
   rangeWithOptions ,
+  clamp ,
 }
 /* No side effect */

src/Core__Int.res

@@ -66,3 +66,14 @@ let rangeWithOptions = (start, end, options) => {
 }
 
 let range = (start, end) => rangeWithOptions(start, end, {})
+
+let clamp = (~min=?, ~max=?, value) => {
+  let value = switch max {
+  | Some(max) if max < value => max
+  | _ => value
+  }
+  switch min {
+  | Some(min) if min > value => min
+  | _ => value
+  }
+}

src/Core__Int.resi

@@ -326,3 +326,19 @@ Int.rangeWithOptions(3, 6, {step: -2}) // RangeError
 - Raises `RangeError` if `step == 0 && start != end`.
 */
 let rangeWithOptions: (int, int, rangeOptions) => array<int>
+
+/**
+`clamp(~min=?, ~max=?, value)` returns `value`, optionally bounded by `min` and `max`.
+
+if `max` < `min` returns `min`.
+
+## Examples
+
+```rescript
+Int.clamp(42) == 42
+Int.clamp(42, ~min=50) == 50
+Int.clamp(42, ~max=40) == 40
+Int.clamp(42, ~min=50, ~max=40) == 50
+```
+*/
+let clamp: (~min: int=?, ~max: int=?, int) => int

test/IntTests.mjs

@@ -459,6 +459,96 @@ Test.run([
       -5
     ]);
 
+Test.run([
+      [
+        "IntTests.res",
+        165,
+        20,
+        27
+      ],
+      "clamp"
+    ], Core__Int.clamp(undefined, undefined, 42), eq, 42);
+
+Test.run([
+      [
+        "IntTests.res",
+        166,
+        20,
+        35
+      ],
+      "clamp - < min"
+    ], Core__Int.clamp(50, undefined, 42), eq, 50);
+
+Test.run([
+      [
+        "IntTests.res",
+        167,
+        20,
+        35
+      ],
+      "clamp - > min"
+    ], Core__Int.clamp(40, undefined, 42), eq, 42);
+
+Test.run([
+      [
+        "IntTests.res",
+        168,
+        20,
+        35
+      ],
+      "clamp - < max"
+    ], Core__Int.clamp(undefined, 50, 42), eq, 42);
+
+Test.run([
+      [
+        "IntTests.res",
+        169,
+        20,
+        35
+      ],
+      "clamp - > max"
+    ], Core__Int.clamp(undefined, 40, 42), eq, 40);
+
+Test.run([
+      [
+        "IntTests.res",
+        170,
+        20,
+        42
+      ],
+      "clamp - < min, < max"
+    ], Core__Int.clamp(50, 60, 42), eq, 50);
+
+Test.run([
+      [
+        "IntTests.res",
+        171,
+        20,
+        42
+      ],
+      "clamp - < min, > max"
+    ], Core__Int.clamp(50, 40, 42), eq, 50);
+
+Test.run([
+      [
+        "IntTests.res",
+        172,
+        20,
+        42
+      ],
+      "clamp - > min, < max"
+    ], Core__Int.clamp(40, 60, 42), eq, 42);
+
+Test.run([
+      [
+        "IntTests.res",
+        173,
+        20,
+        42
+      ],
+      "clamp - > min, > max"
+    ], Core__Int.clamp(40, 40, 42), eq, 40);
+
 export {
   eq ,
   $$catch ,

test/IntTests.res

@@ -161,3 +161,13 @@ Test.run(
   eq,
   [-3, -5],
 )
+
+Test.run(__POS_OF__("clamp"), Int.clamp(42), eq, 42)
+Test.run(__POS_OF__("clamp - < min"), Int.clamp(~min=50, 42), eq, 50)
+Test.run(__POS_OF__("clamp - > min"), Int.clamp(~min=40, 42), eq, 42)
+Test.run(__POS_OF__("clamp - < max"), Int.clamp(~max=50, 42), eq, 42)
+Test.run(__POS_OF__("clamp - > max"), Int.clamp(~max=40, 42), eq, 40)
+Test.run(__POS_OF__("clamp - < min, < max"), Int.clamp(~min=50, ~max=60, 42), eq, 50)
+Test.run(__POS_OF__("clamp - < min, > max"), Int.clamp(~min=50, ~max=40, 42), eq, 50) // min wins
+Test.run(__POS_OF__("clamp - > min, < max"), Int.clamp(~min=40, ~max=60, 42), eq, 42)
+Test.run(__POS_OF__("clamp - > min, > max"), Int.clamp(~min=40, ~max=40, 42), eq, 40)