luatex.pdf v 1.15 p 24, reads
"The most simple use of these is tex.print(<string> s)"
Next examples on the same page read
"tex.print(tex.count[10]+5)"
and
"tex.print(math.pi)"
Both arguments are not strings: this is an unrelated and undocumented usage of
"tex.print" that would deserve a note in the appropriate section
According to the documentation p201, next instruction
\directlua{tex.print({‘1’, 2, ‘3'})}
should stop printing at 2 because it is not a string.
Actually it prints all the elements of the table, at least in luatex 1.13.2
