From c6f7ed0a4b867014da72ed05ed3de59d23e01567 Mon Sep 17 00:00:00 2001
From: Andy Ferris <ferris.andy@gmail.com>
Date: Mon, 16 Oct 2017 21:47:29 +1000
Subject: [PATCH] EnvHash should be immutable

This is a bit of a relic, and was never really updated to be a standard immutable singleton. I doubt there is a lot of practical difference, but hey.

FYI this type so old, it is now the *second* time it is called a `struct`. :)
---
 base/env.jl | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/base/env.jl b/base/env.jl
index 73e1ff87bf0a3..a3302da12f152 100644
--- a/base/env.jl
+++ b/base/env.jl
@@ -63,7 +63,7 @@ end # os test
 
 A singleton of this type provides a hash table interface to environment variables.
 """
-mutable struct EnvHash <: Associative{String,String}; end
+struct EnvHash <: Associative{String,String}; end
 
 """
     ENV