From 300dd89c9b9c3a98802ea8bb4c8afd4492f8fba5 Mon Sep 17 00:00:00 2001
From: andys8 <andys8@users.noreply.github.com>
Date: Tue, 10 May 2022 16:38:27 +0200
Subject: [PATCH] React.memo with argument

Adding another variant of memo that allows passing a function to compare
previous and new props.

<https://reactjs.org/docs/react-api.html#reactmemo>

Solves <https://github.com/megamaddu/purescript-react-basic-hooks/issues/60>
---
 src/React/Basic/Hooks.js   |  1 +
 src/React/Basic/Hooks.purs | 18 ++++++++++++++++++
 2 files changed, 19 insertions(+)

diff --git a/src/React/Basic/Hooks.js b/src/React/Basic/Hooks.js
index a285755..e699f76 100644
--- a/src/React/Basic/Hooks.js
+++ b/src/React/Basic/Hooks.js
@@ -13,6 +13,7 @@ const useEqCache = (eq, a) => {
 exports.reactChildrenToArray = (children) => React.Children.toArray(children);
 
 exports.memo_ = React.memo;
+exports.memoEq_ = React.memo;
 
 exports.useState_ = (tuple, initialState) => {
   const r = React.useState(
diff --git a/src/React/Basic/Hooks.purs b/src/React/Basic/Hooks.purs
index 4bb46ab..02470e2 100644
--- a/src/React/Basic/Hooks.purs
+++ b/src/React/Basic/Hooks.purs
@@ -8,6 +8,7 @@ module React.Basic.Hooks
   , reactChildrenToArray
   , reactChildrenFromArray
   , memo
+  , memo'
   , useState
   , useState'
   , UseState
@@ -166,6 +167,16 @@ memo ::
   Effect (ReactComponent props)
 memo = flip Prelude.bind (runEffectFn1 memo_)
 
+-- | Similar to `memo` but takes a function to compare previous and new props
+memo' ::
+  forall props.
+  (props -> props -> Boolean) ->
+  Effect (ReactComponent props) ->
+  Effect (ReactComponent props)
+memo' arePropsEqual comp = Prelude.do
+  c <- comp
+  runEffectFn2 memoEq_ c (mkFn2 arePropsEqual)
+
 useState ::
   forall state.
   state ->
@@ -359,6 +370,13 @@ foreign import memo_ ::
     (ReactComponent props)
     (ReactComponent props)
 
+foreign import memoEq_ ::
+  forall props.
+  EffectFn2
+    (ReactComponent props)
+    (Fn2 props props Boolean)
+    (ReactComponent props)
+
 foreign import unsafeSetDisplayName ::
   forall props.
   EffectFn2 String (ReactComponent props) (ReactComponent props)