Up to now, we tolerated null pointers in Literal instances.
But we can not tolerate passing a null cString to Symbol initialisation.
Rather, hereby we introduce a dedicated "bottom" Symbol, a valid "null object"
For this task, I've also investigated to use boost::operators
This would only incur a negligible penalty on build times and executable sizes,
however, I don't consider the boost based solution to improve readability,
since many of these comparisons are tricky or subtly different.
Moreover, since boost::operators needs to be mixed-in, the initialisation
of Symbol objects becomes difficult, not to mention the additional base class
information visible in the debugger when inspecting Symbol or Literal objects
For that reason, I decided *against* using Boost here and coded up
all the operators in all combinations manually
...which means, from now on identical input strings
will produce the same Symbol object (embedded pointer).
TODO: does not handle null pointers passed in as c-String properly
just by reasoning from the concept, an instance should always correspond
to a single invocation trail. Having several sets of invocation state
compete with each other, means to keep them distinct, otherwise the
implicit state is going to be corrupted
obsoleted by C++11
* in most cases, it can be replaced by an explicit conversion operator
* especially for the Lumiera Forward Iterators, we need an implicit conversion
This changeset fixes a huge pile of problems, as indicated in the
error log of the Doxygen run after merging all the recent Doxygen improvements
unfortunately, auto-linking does still not work at various places.
There is no clear indication what might be the problem.
Possibly the rather unstable Sqlite support in this Doxygen version
is the cause. Anyway, needs to be investigated further.
this is indeed a change of concept.
A 'command instance' can not be found through the official
Command front-end anymore, since we do not create a registration.
This allows us to avoid decorating command IDs with running counters
interesting new twist: we do not even need to decorate with a running number,
since we'll get away with an anonymous command instance, thanks to Command
being a smart-handle
it is not *that* hard to behave in a somewhat sane manner here.
And even more: this *is* basically the symbol table implementation we need.
Thus we only need to build the right front-end now...
...otherwise our log will be flooded with command definition messages soon
NOTE: to see all command definitions happening, set into environment:
NOBUG_LOG='command:TRACE
this is a prerequisite for command instance management:
We have now an (almost) complete framework for writing actual
command definitions in practice, which will be registered automatically.
This could be complemented (future work) by a script in the build process
to regenerate proc/cmd.hpp based on the IDs of those automatic definitions.
...better make it noncopyable to enforce the builder-style use.
In the recent test, I observed strange behaviour when erroneously passing
the CommandDef by value; the command seemed to be registered just fine,
but afterwards, the registry was empty. I must admit I don't understand
this, just from reading the code in CommandDef and Command it should
work just fine to activate a copy of the originally started CommandDef;
anyway, I didn't care to track that issue down, rather make the
CommandDef noncopyable as it should have been right from start.
...since there is not any test coverage for this trait, which
turned out to be quite deeply rooted in the system by now and
handles several rather subtle special cases
...and move the tail-call of the template instantiation into try.cpp
This experiment clearly shows the discrepancy now:
- binding a member pointer directly into a function object will expand the argument list
- but binding a similar lambda into a function object won't
(it is not necessary due to the context capture)
The result is that we need to drop support for one of those cases,
and it is clear that the member poiter will be the looser...
As a first step towards a gradual rework of our function metaprogramming helpers,
this change prepends a generic case for all kinds of functors to our existing
solution, which up to now was entirely based on explicit specialisations.
C++11 supplied the new language construct 'decltype(EXPR)', which allows us
to capture any class with an function operator, which also includes the Lambdas.
The solution was proposed 2011 on StackOverflow
http://stackoverflow.com/questions/7943525/is-it-possible-to-figure-out-the-parameter-type-and-return-type-of-a-lambda/7943765#7943765
We used it already with success within our TreeMutator.
But obviously the goal should be to unite all the function trait / metaprogramming helpers,
which unfortunately is a more expensive undertaking, since it also involves
to get rid of the explicit specialisations and retrofit our Types<XXX...> helper
to rely on variadic templates rather than on loki-style typelists.
This first step here is rather conservative, since we'll still rely on our
explicit specialisations in most cases. Only the Lambdas will go through the
new, generic case, and from there invoke the specialisation for member functions.
The latter need to be rectified as well, which is subject of the next changeset...
The point in question is how to manage these definitions in practice,
since we're about to create a huge lot of them eventually. The solution
attempted here is heavily inspired by the boost-test framework
...because this topic serves as a vehicle to elaborate various core concepts
of the UI backbone, especially how to access, bind and invoke Proc-Layer commands
this pretty much resolves most of the uncertainities:
we now get a set of mutually dependent services, each of which
is aware of each other member's capabilities, but accesses those
only through this partner's API
Idea is to use the window list, which should hold any workspace window
ever created, and pick the first one marked as 'active' by GTK
(whatever that means)
After quite some pondering, it occured to me that we both
- need some top-level model::Tangible to correspond to the RootMO in the session
- need some Controller to handle globally relevant actions
- need a way to link action invocation to transient interaction state (like focus)
This leads to the introduction of a new top-level controller, which is better
suited to fill that role than the depreacted model-controller or the demoted window-manager
looks like we're in management business here ;-)
we chop off heads, slaughter the holy cows and then install -- a new manager
...allows us to get rid of a lot of sigc boilerplate syntax.
The downside is that the resulting functors are not sigc::trackable.
This seems adequate here, since the whole top-level UI backbone is
maintained by GtkLumiera, and thus ensured to exist as long as the
main GTK event loop is running.
WARNING: beware of creating "wild" background thrads in the UI, without
proper scheduling of any communication via the event loop!
no need for a further translation unit,
rather, definition of global menu now becomes part of the
ui-manager.cpp translation unit, which allows for some additional
inlining and simplifications by the compiler
it turns out to be essentially an implementation detail,
it is a builder class and it acts as closure for the bound
menu actions, but it is not accessed after initialisation.
This allows to reduce the header inclusion load significantly
This is a very pervasive change and basically turns the whole top-level
of the GTK-UI bottom-up. If this change turns out right, it would likely
solve #1048
WARNING: in parts not implemented, breaks UI
...which itself is obsolete and needs to be redesigned from scratch.
For now we create a local instance of this obsolete PlaybackController
in each viewer panel and we use a static accessor function to just some
instance. Which would break if we start playback with multiple viewer
panels. But we can't anyway, since the Player itself is also a broken
leftover from an obsoleted design study from the early days.
so why care...
unfortunately boost/program-options make the boost reference-wrapper visible
And it doesn't help to alias to std::ref at the definition site of the
problematic function (in TimeControl), because this itself is picked up
via ADL
So this is not really a solution, rather a workaround, in the hope
that boost will clean-up this ambiguity eventually
as a rule, one should not rely on "using namespace xyz",
since this makes organisation of minimal header includes near impossible.
You end up with mass includes in some "top level" headers, resulting
in painfully slow compilation turnaround times.
In exceptional cases, using namespace foo might be adequate though
- WindowList (ex WindowManager)
- Project & Controller
the latter ones are defunct and can be replicated down into each
of the old timeline pannel instances. They just serve the purpose
to keep this old code barely functional, so it can be used as reference
for building the new timeline
There seems to be a mismatch in the arrangement of the top-level entities
* we support multiple windows, yet from reading the code, you'd ge the impression we aren't really aware we have multiple top-level windows
* the `WindowManager` is the core UI manager, which feels like a mix-up in concerns
* the `WorkspaceWindow::createUI()` does the global UI initialisation. Again, we have multiple workspace windows.
* `GtkLumiera::main()` creates a `Model` and a `Controller` in local function scope, but stores the `WindowManager` in an object field.
* it seems, for that very reason, `GtlLumiera` needed to be a singleton, to allow by-name access to "the" `WindowManager`
* needless to say, this causes a host of problems when shutting down the UI.
The idea is to introduce a dedicated UiManager, to deal with the central
framework induced concerns solely, and to demote the WindowManager and the
WorkspaceWindows to care only for their local concerns
in fact it just does not fulfil any of the behavioural properties
of a full-fledged UI-Element. All it needs is an uplink bus connection,
so let's just keep it as that
Sidenote: I've realised today that such a "free standing" BusTerm
without registration in Nexus is a good idea and acceptable solution.
yes, it's a cycle and indeed quite tricky.
Just verified it (again) with the debugger and saw all
dtor calls happening in the expected order. Also the number
of Nexus registration is sane
Now I've realised that there are two degrees of connectedness.
It is very much possible to have a "free standing" BusTerm, which
only allows to send uplink messages. In fact, this is how CoreService
is implemented, and probably it should also the way how to connect
the GuiNotification service...
due to investigating that Heisenbug, I understand the storage layout
more clearly. It occured to me that there is no reason to copy the
terminationHandler (functor) into an instance variable, since it is
easily possible to keep all of the invocation and error handling
confined within the scope of the run function, i.e. on stack.
So the effective memory layout does not change, but the legibility
of the code is improved, since we're able to remove the dtor and
simplyfy the ctor and avoid most of the member fields.
Reason was some insideous detail regarding Lambdas:
When a Lambda captures context, a *closure* is created.
And while the Lambda itself is generated code, pretty much
like an anonymous function, the closure depends on the context
that was captured. In our case here, the Lambda used to start
the thread was the problem: it captured the termCallback functor
from the argument of the enclosing function. In fact it did not
help or change anything if we successively package that lambda
into a function objet and store this by value, because the
lambda still refers to the transient function context present
on stack at the moment it was captured.
The solution is to revert back to a bind expression, since this
creates a dedicated storage for the bound function arguments
managed within the bind-functor. This makes us independent
from the call context
...because some Bus connections stem from elements which are
member of CoreService, thus the'll still be connected when the
sanity check in the dtor runs
But even with this fix, we still get a SEGFAULT
TODO
- is this actually a sensible idea, from a design viewpoint?
- in which way to bind GuiNotification for receiving diff messages?
- Problem with disconnnecting from Nexus on shutdown
