From 0d11887c222ca23ec3f4a50e46fd36de6e568942 Mon Sep 17 00:00:00 2001
From: samcv <samantham@posteo.net>
Date: Tue, 18 Oct 2016 09:59:13 -0700
Subject: [PATCH] =?UTF-8?q?Perl6:=20Explain=20that=20Integers=20Can't=20be?=
 =?UTF-8?q?=20Passed=20and=20Modified=20in=20Sub's=20Even=20If=20Using=20`?=
 =?UTF-8?q?is=20rw=C2=B4=20(#2471)?=
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* Explain that you cannot pass immutable values like integers to subs even if you use $n is rw.

* Add myself as a contributor

* Remove contributor since I am not a major contributor
---
 perl6.html.markdown | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/perl6.html.markdown b/perl6.html.markdown
index b5a25a41..54feeee7 100644
--- a/perl6.html.markdown
+++ b/perl6.html.markdown
@@ -193,6 +193,15 @@ sub mutate($n is rw) {
   say "\$n is now $n !";
 }
 
+my $m = 42;
+mutate $m; # $n is now 43 !
+
+# This works because we are passing the container $m to mutate.  If we try
+# to just pass a number instead of passing a variable it won't work because
+# there is no container being passed and integers are immutable by themselves:
+
+mutate 42; # Parameter '$n' expected a writable container, but got Int value
+
 # If what you want a copy instead, use `is copy`.
 
 # A sub itself returns a container, which means it can be marked as rw: