The most consolidated macro you can come across is if you install the addon
https://github.com/DennisWG/CastModifier
and your macro becomes...
/cast !Attack
Although i kinda feel that the above addon is exclusive to supermacro.
Edit: There is also a new addon from Aviana called classic macros that actually has a /startattack
https://github.com/Aviana/ClassicMacros