class Tilt::Template

def require_template_library(name)

running under a threaded environment.
Like Kernel::require but issues a warning urging a manual require when

def require_template_library(name)
  if Thread.list.size > 1
    warn "WARN: tilt autoloading '#{name}' in a non thread-safe way; " +
         "explicit require '#{name}' suggested."
  end
  require name
end