lexical shapes that describe the environment *

constant shape representing the empty class *

generates an object shape containing a given property map *

generates a class object shape containing a new prototype object *

generates a fresh id *

Example: string_of_shape indent shape *

parse info for JS files, containing an AST and a token list with comments *

map of file names to parse info cached after parsing *

local info computed per module, containing exports and local shapes *

map of module names to module info cached after analysis *