385     def eval(self, env):  member in Expr
393     def eval(self, env):  member in String
431     def eval(self, env):  member in Bool
474     def eval(self, env):  member in Integer
494     def eval(self, env):  member in VarRef
497             return env[self.name].eval(env)
498         return self.value.eval(env)
504     def eval(self, env):  member in List
506         return List(item.eval(env) for item in self)
518     def eval(self, env):  member in Dict
520         return Dict((key, value.eval(env)) for key, value in self.items())
539     def eval(self, env):  member in Concat
541         lhs = self.lhs.eval(env)
542         rhs = self.rhs.eval(env)
791                         for filename in env['build'].eval(env))
796                 for path in env['subdirs'].eval(env):
800                 for path in env['optional_subdirs'].eval(env):
820             modules = [(ident, attrs.eval(env)) for ident, attrs in modules]