The meaning of different GC parameters changed, so there is point in
supporting old values for them. The new code simply ignores the
parameters when changing the GC mode, so the incompatibility is small.
The generational mode also uses the parameters for the incremental
mode in its major collections, so it should be easy to change those
parameters without having to change the GC mode.
Any C function can receive maxinteger as an integer argument, and
therefore cannot increment it without some care (e.g., doing unsigned
arithmetic as the core does).
More uses of macros 'likely'/'unlikely' (renamed to
'l_likely'/'l_unlikely'), both in range (extended to the
libraries) and in scope (extended to hooks, stack growth).
The macro 'luaL_pushfail' documents all places in the standard libraries
that return nil to signal some kind of failure. It is defined as
'lua_pushnil'. The manual also got a notation (@fail) to document those
returns. The tests were changed to be agnostic regarding whether 'fail'
is 'nil' or 'false'.
Added the concept of control messages to the warning system, plus the
implementation of the controls "@on"/"@off" to turn warnings on/off.
Moreover, the warning system in the test library adds some other
controls to ease the test of warnings.
Instead of a 'tocont' flag, the function 'warn' in Lua now receives all
message pieces as multiple arguments in a single call. Besides being
simpler to use, this implementation ensures that Lua code cannot create
unfinished warnings.
- The warning functions get an extra parameter that tells whether
message is to be continued (instead of using end-of-lines as a signal).
- The user data for the warning function is a regular value, instead
of a writable slot inside the Lua state.
- in 'luaB_tonumber', do not need to "checkany" when argument
is a number.
- in 'lua_resume', the call to 'luaD_rawrunprotected' cannot return
a status equal to -1.
New auxiliary functions/macros 'luaL_argexpected'/'luaL_typeerror'
ease the creation of error messages such as
bad argument #2 to 'setmetatable' (nil or table expected, got boolean)
(The novelty being the "got boolean" part...)
Some simplifications (not counting bytes, couting only slots visited;
no more 'gcfinnum'); more GC parameters; using vararg in 'lua_gc' to
set parameters in different GC modes
