the parent class for all of our syntactical objects
Required files
puppet
puppet/util/autoload
puppet/file_collection/lookup
puppet/parser/ast/arithmetic_operator
puppet/parser/ast/astarray
puppet/parser/ast/branch
puppet/parser/ast/boolean_operator
puppet/parser/ast/caseopt
puppet/parser/ast/casestatement
puppet/parser/ast/collection
puppet/parser/ast/collexpr
puppet/parser/ast/comparison_operator
puppet/parser/ast/definition
puppet/parser/ast/else
puppet/parser/ast/function
puppet/parser/ast/hostclass
puppet/parser/ast/ifstatement
puppet/parser/ast/leaf
puppet/parser/ast/match_operator
puppet/parser/ast/minus
puppet/parser/ast/node
puppet/parser/ast/nop
puppet/parser/ast/not
puppet/parser/ast/resource
puppet/parser/ast/resource_defaults
puppet/parser/ast/resource_override
puppet/parser/ast/resource_reference
puppet/parser/ast/resourceparam
puppet/parser/ast/selector
puppet/parser/ast/tag
puppet/parser/ast/vardef