Environment classes for atomic propositions

Classes
class	spot::declarative_environment
	A declarative environment. More...
class	spot::default_environment
	A laxist environment. More...
class	spot::environment
	An environment that describes atomic propositions. More...

Detailed Description

Environment classes can be passed to the parser to interpret and restrict the set of atomic propositions. For instance, the default_environment will allow all atomic propositions, while the declarative_environment will allow only a predeclared set of atomic propositions.