From 0aca0666a304983d145efb764c39a6952af7664a Mon Sep 17 00:00:00 2001
From: lulalala <mark@goodlife.tw>
Date: Thu, 9 Nov 2017 23:00:50 +0800
Subject: [PATCH] Document about lambda return value also being interpolated

---
 lib/i18n.rb | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/lib/i18n.rb b/lib/i18n.rb
index d79b661e..c3d97367 100644
--- a/lib/i18n.rb
+++ b/lib/i18n.rb
@@ -144,6 +144,10 @@ def reload!
     #
     # Then <tt>I18n.t(:salutation, :gender => 'w', :name => 'Smith') will result in "Mrs. Smith".
     #
+    # Note that the string returned by lambda will go through string interpolation too,
+    # so the following lambda would give the same result:
+    #   lambda { |key, options| options[:gender] == 'm' ? "Mr. %{name}" : "Mrs. %{name}" }
+    #
     # It is recommended to use/implement lambdas in an "idempotent" way. E.g. when
     # a cache layer is put in front of I18n.translate it will generate a cache key
     # from the argument values passed to #translate. Therefor your lambdas should