string literals lack string methods - why?

["Dr. Markus Walther" <walther@...>]

Hi all,

Lua has been said to operate by the principle of 'least surprise' -

but I was surprised that string methods apply to string variables, but
raise an exception with literals:

s = "abcd" ; print(s:match("^%x%x"))

vs.

print("abcd":match("^%x%x"))

I guess I mentally apply a kind of
instantiation-doesn't-change-semantics principle here, hence the surprise.

Question: any deeper reasons for the above behaviour? Can/should this be
rectified?

--Markus