doc: add an example about multiple extensions

`path.extname` returns only the last extension

diff --git a/doc/api/path.markdown b/doc/api/path.markdown
index fe59134..e01fa8b 100644 (file)
--- a/doc/api/path.markdown
+++ b/doc/api/path.markdown
@@ -133,6 +133,10 @@ an empty string.  Examples:
     // returns
     '.html'
 
+    path.extname('index.coffee.md')
+    // returns
+    '.md'
+
     path.extname('index.')
     // returns
     '.'