Mention Ruby version requirement in Readme

st0012 · ko1 · commit d3a9e5b3d826 · 2022-02-22T03:45:15.000+09:00
diff --git a/README.md b/README.md
@@ -2,7 +2,7 @@
 
 # debug.rb
 
-This library provides debugging functionality to Ruby.
+This library provides debugging functionality to `Ruby MRI 2.6+`.
 
 This debug.rb is replacement of traditional lib/debug.rb standard library which is implemented by `set_trace_func`.
 New debug.rb has several advantages:
diff --git a/misc/README.md.erb b/misc/README.md.erb
@@ -2,7 +2,7 @@
 
 # debug.rb
 
-This library provides debugging functionality to Ruby.
+This library provides debugging functionality to `Ruby MRI 2.6+`.
 
 This debug.rb is replacement of traditional lib/debug.rb standard library which is implemented by `set_trace_func`.
 New debug.rb has several advantages:
