Pushes the current indentation state of the Verbose object, which is controlled by *enter() and
*exit(). By pushing the state when entering a function and
using on.exit() to pop the state, the correct state will
set regardless of if the functions returned naturally or via an error.
# S3 method for Verbose
pushState(this, ...)Not used.
Returns (invisibly) TRUE.
For more information see Verbose.