_ACTION
The _ACTION global variable stores the name of the action to be performed on this execution run. As an example, if this command line was used to launch Premake:
$ premake5 vs2013
...then _ACTION will be set to "vs2013". If there is no action (for instance, if the command was premake5 --help) this variable will be nil.
Availability
Premake 4.0 or later.