naming: Why luaL_testudata but lua(L)_to*?

[nobody <nobody+lua-list@...>]

Hey *,

why is it that all error-throwing getters are called lua(L)_check*,
almost all getters that signal errors by their return value are called
lua(L)_to*, but it's luaL_testudata and not luaL_toudata?

Is there a deeper reason or is it just accidental?

-- nobody