This is an extremely extensive patch as it hits every cvar, and every
usage of the cvars. Cvars no longer store the value they control,
instead, they use a cexpr value object to reference the value and
specify the value's type (currently, a null type is used for strings).
Non-string cvars are passed through cexpr, allowing expressions in the
cvars' settings. Also, cvars have returned to an enhanced version of the
original (id quake) registration scheme.
As a minor benefit, relevant code having direct access to the
cvar-controlled variables is probably a slight optimization as it
removed a pointer dereference, and the variables can be located for data
locality.
The static cvar descriptors are made private as an additional safety
layer, though there's nothing stopping external modification via
Cvar_FindVar (which is needed for adding listeners).
While not used yet (partly due to working out the design), cvars can
have a validation function.
Registering a cvar allows a primary listener (and its data) to be
specified: it will always be called first when the cvar is modified. The
combination of proper listeners and direct access to the controlled
variable greatly simplifies the more complex cvar interactions as much
less null checking is required, and there's no need for one cvar's
callback to call another's.
nq-x11 is known to work at least well enough for the demos. More testing
will come.
GIB. Added some breakpoint GIB builtins for debugging script/intepreter
interactions. Made carne work properly again (local variables don't
disappear in interactive mode)
changes. There still remains some bugs to be squashed, a feature or two to
add, and some polishing to be done. However, it seems to be in a workable
state.
parser a bit to accomodate this. Backslashes in double quotes are now only
removed if they escape a character that can't be written normally, or
another backslash. Removed start position support from string::findsub
since variable slices can be used instead. Added support for regular
expressions in the form of regex::match, regex::replace, and
regex::extract. Checked in regex.c from GNU regex 0.12 for platforms that
do not have regex functions in their standard library. Two minor changes
were made to this file to fix gcc warnings. Prepared the path transform
function for a change to a filesystem rooted at fs_userpath instead of the
current gamedir, but these changes are commented out pending security
considerations.
