As per the discussion in https://github.com/scp-fs2open/fs2open.github.com/issues/2092,
if you specify the turn time, these can behave quite weirdly.
Some mods that we don't want to break backwards compatability with use
that mode, but at least we can note the pitfalls in help.
This re-implements the eval_nums function to use C varargs, instead of C++11 template parameter packs. This is necessary because Visual Studio has a bug where template parameter packs corrupt heap memory somehow.
NaN should propagate through the SEXP tree, but not all SEXPs do this properly. The problem was made worse after I introducted `eval_num()` which silently ignored NaN values. This commit adds new boolean arguments to `eval_num()` to flag NaN results, and changes all calls of `eval_num()` to properly handle the new arguments. Additionally, this adds `eval_nums()` and `eval_array()` functions to more smoothly handle cases where many numbers appear in a row.
In single-player, or while running as a server, sexp_deal_with_ship_flag() makes sure that object_flag, ship_flag, and p_object_flag aren't NUM_VALUES (i.e. not set) before trying to call flags.set() with them. However, the client code in multi_sexp_deal_with_ship_flag() had no such security checks, and as such would try to set NUM_VALUES, which is outside the range of valid flags; this led to a crash in Release builds and an Assertion otherwise.
This PR adds a sexp that returns the integer value of a ship or wing hotkey. No hotkey returns -1, F5 returns 0, F6 returns 1, ... and the sexp takes one arguemnt, the ship or wing name.
This new sexp allows a FREDer to set a hotkey for a ship or wing. The sexp takes 2 or more arguemnts, the integer of the hotkey to set (F5=0, F6=1, ... F12=7) and the names of the ship(s) and/or wing(s).
Tom Crayford