[ruby/pp] Reduce substring creations

https://github.com/ruby/pp/commit/fee2d39099

1 files changed, 3 insertions, 5 deletions

diff --git a/lib/pp.rb b/lib/pp.rb
index 2c7f41eadd..e790f499d4 100644
--- a/lib/pp.rb
+++ b/lib/pp.rb
@@ -313,12 +313,10 @@ class PP < PrettyPrint
       # A pretty print for a pair of Hash
       def pp_hash_pair(k, v)
         if Symbol === k
-          sym_s = k.inspect
-          if sym_s[1].match?(/["$@!]/) || sym_s[-1].match?(/[%&*+\-\/<=>@\]^`|~]/)
-            text "#{k.to_s.inspect}:"
-          else
-            text "#{k}:"
+          if k.inspect.match?(%r[\A:["$@!]|[%&*+\-\/<=>@\]^`|~]\z])
+            k = k.to_s.inspect
           end
+          text "#{k}:"
         else
           pp k
           text ' '