Install yasnippet and vala-snippets packages

elpa/yasnippet-20160924.2001/snippets/lisp-mode/do

@@ -0,0 +1,9 @@
+# -*- mode: snippet -*-
+# name: do
+# key: do
+# --
+(do ((${1:var1} ${2:init-form} ${3:step-form})
+     (${4:var2} ${5:init-form} ${6:step-form}))  
+    (${7:condition} ${8:return-value})
+    (${9:body}))
+$0