From 3cb942c5903b16a4e75a02cb60210f47b8353b65 Mon Sep 17 00:00:00 2001
From: Laszlo Szenes <42390521+lacikawiz@users.noreply.github.com>
Date: Wed, 24 Apr 2019 06:45:11 -0400
Subject: [PATCH] Clarifying passing params to event handler

In Svelte 3, event handler calls work differently than in v2. It's important to detail the difference and provide explanation of how it works.
---
 .../tutorial/05-events/01-dom-events/text.md   | 18 +++++++++++++++++-
 1 file changed, 17 insertions(+), 1 deletion(-)

diff --git a/site/content/tutorial/05-events/01-dom-events/text.md b/site/content/tutorial/05-events/01-dom-events/text.md
index 1c08c9159a..b8e3b9fef9 100644
--- a/site/content/tutorial/05-events/01-dom-events/text.md
+++ b/site/content/tutorial/05-events/01-dom-events/text.md
@@ -8,4 +8,20 @@ As we've briefly seen already, you can listen to any event on an element with th
 <div on:mousemove={handleMousemove}>
 	The mouse position is {m.x} x {m.y}
 </div>
-```
\ No newline at end of file
+```
+
+> The `on:` directive expects a function reference in the curly braces. *Not a function call as it was in version 2*. 
+> When the event is triggered the function will be called with the `event` object as the first parameter.
+> So if you need to pass a value with the event then you need to make a function that returns a function with your parameter enclosed. Here is an example:
+```html
+<script>
+	let sum=0
+	function add(val){
+		return function(){ sum+=val }
+	}
+	//Or you can use the arrow functions : 
+	//const add= val => () => sum+=val 
+</script>
+...
+<button on:click={add(2)}>Add 2 to the sum</button>
+```