sans the implementation of the index lookup table(s)
The algorithm is KISS, a variant of insertion sort, i.e.
worst time quadratic, but known to perform well on small data sets.
The mere generation of the diff description is O(n log n), since
we do not verify that we can "find" out of order elements. We leave
this to the consumer of the diff, which at this point has to scan
into the rest of the data sequence (leading to quadratic complexity)
finally....
The problem is that the C++ "dependent types" defeat the typical
DSL usage, where you define some helper function in a generic
language setup class and mix this language in as superclass.
This is, C++ requires us to refer explicitly to any dependent type,
since, due to possible template specialisations, the parser
can't know if a given symbol is a inherited type or a field.
As a solution, we place the token constructor functors into a
static struct "token", which allows to write e.g. token.insert(xyz)
As decided in beb57cde
this changeset switches our basic list diff language to work
in the style of an insertion sort. Rather than 'pushing back'
out-of-order elements, we scan and bring forward missing elements.
Later, when passing the original location of the elements
fetched this way, a 'skip' verb will help to clean up
possible leftowers, so implementation is possible
(and indeed acomplished) without shifting any other elements.
we want a simple and straight forward way of defining tokens
of the "diff language". Each token is bound to a specific
handler function in the language interpreter interface.
Problem is that likely we'll get a ListDiffLanguage and a TreeDiffLanguage;
after all, I really don't know yet how far to take this whole
diff representation endeavour...
Basically attempt to represent the individual diff step
as a tuple of "DiffVerb" and reference element.
The meaning of the reference element depends on the actual verb
...first step is to design a generic linearised list diff representation.
Basically just need to pull together the theoretical work of the last weeks.
Next steps will be to extend to typed ordered trees.
Heureka! found out that the C++ standard library exposes a
cross vendor C++ ABI, which amongst others allows to show
object code names and type-IDs in the language-level, human
readable unmangeld form.
Of course, actual application code should not rely on such a
internal representation, yet it is of tremendous help when
writing and debugging unit tests.
Signed-off-by: Ichthyostega <prg@ichthyostega.de>
the idea ist to build some kind of "smart" enum constants,
which allow for double dispatch through a member function pointer,
invoking a virtual function on a common handler interface
Actually I arried at the conclusion, that the *receiving* of
a diff representation is actually a typical double-dispatch situation.
This leads to the attempt to come up with a specialised visitor
as standard pattern to handle and apply a diff. Obviously,
we do not want the classical GoF-Visitor, but (yes, we had
that discussion allready) -- well in terms of runtime cost,
we have to deal with at least two indirections anyway;
so now I'm exploring the idea to implement one of these
indirections through a functor object, which at the same time
acts as "Tag" in the diff representation language (instead
of using an enum as tag)
Uniform sequence at start of source files
- copyright claim
- license
- file comment
- header guard
- lumiera includes
- library / system includes
Lumiera uses Brittish spelling. Add an according note to the styleguide.
initial considerations; there is a concurrency problem, since
all of session handling within Proc is deliberately not threadsafe.
Thus the decision is to make this the gui::model::SessionFacade's responsibility
- the tests covering threadind support and object monitors
are located in the backend test-library and linked against liblumierabackend.so
- some fundamental facilities of proc-layer moved from the library tree
into the basic components tree, since *testing* them requires at least
to link against liblumieracommon.so
here we're iterating hash table based collections, consequently
the order of items retrieved *is* implementation dependent and indeed
differs on different platforms and compilers.
In Clang, static object fields are initialised from top to bottom,
but before any other variables in anoymous namespaces. To the contrary,
GCC evaluates *any* initialisation expression in the translation
unit together from top to bottom. Thus, in the clang generated
code, in two cases the static initialisation could use a not yet
constructed local lib::_Fmt formatter object.
the use of a custom finisihing functor, which is applied
to any generated product. This can be used for registration,
memory management or similar framework aspects
Implement the first simple usage scenario for the
unified MultiFact template, using variadic templates.
NOTE:
- the obvious solution based on std::forward
triggers strange behaviour in GCC-4.7
- the inline lambda in the test case traps the
CLang-3.0 parster with a segfault. Horay!
right now we have to defeat an unfortunate static assertion in
the standard library, which is expected to go away in the future.
We use a hack to hijack the problematic definition with the preprocessor,
which requires our header to be first.
c++11 uses another hashtable implementation.
This uncovered some poorly written tests, which relied on
objects being returned in a specific order. As far as poissible,
we're using generic query functions now to get our test objects.
But these tests still rely on a specifically crafted test index content,
which as such is acceptable IMHO. The only remaining problem is
that we check the order of generated output in some tests, and this
order is still implementation dependent.
This is a notable difference to the boost or tr1-function objects
we used up to now. Thus the behavour is now straight forward without
any exception. If the function takes an argument by reference,
this is replicated through bind and function expressions
a real fix would be to rewrite the test to collect the retrieved
values and do a structural verification of the results. This
would mean to write a lot of code for such a marginal topic,
which was implemented just for sake of completenes anyway.
Hopefully my lack of "motivation" doesn't backfire eventually ;-)
Conversion means automatic conversion. In our case,
what we need ist the ability to *construct* a bool from
our (function) object -- while functors aren't automatically
convertible to bool. Thus we use one of the new predicates
from <type_traits>
...uncovered by switching to c++11
When invoking an individual test, we used to erase
the 0-th cmdline argument, which happens to be allways
the name of the test being invoked. Yet none of our
tests actually complied to that contract. Rather,
all tests taking arguments access them by 1-based
argument index. Previously, the argument values just
happened to be still in memory at the original location
after erasing the 0st element.
"Fixed" that by changing the contract. Now, the 0th argument
remains in place, but when there are no additional arguments,
the whole cmdline is cleared.
This is messy, but the test runer needs to be rewritten
entirely, the whole API is clumsy and dangerous. Ticket #289
In the November developer meeting, Christian and I agreed that
it's best to remove that offending LUID specifications altogether.
Those embedded LUIDs where one of the issues blocking the transition to C++11
this is rather a workaround.
The problem is a wraparound while calculating the common denominator in
Time rawTime (dirt + frames*F25);
Currently we're using boost_rational<long>, and long is only 32bit
on 32bit platforms. The workaround commited here just avoids
the calculation of the fractional value, and adds 64bit time values
instead. But the real solution would be to use a consistent
approach for dealing with frame counts and frame rates, all
based on 64bit values. See Ticket #939
This is a partial and preliminary fix; we had an occasional
numeric overflow on 32bit platforms in some tests.
The complete fix will be to introduce a typedef and then
rework the relevant APIs (which are preliminary anyway,
thus no urge right now)
our front-end for boost::format, the class lib::_Fmt
was lacking an reliable specialisation for long and ulong.
This is due to the notorious problem of these types being
of platform dependant size. As a fix, we're speclialising
explicitly for int16_t, int32_t and int64_t and avoid the
common names 'short', 'int' and 'long' alltogether.
And especially for non-64bit-platform (NONPORTABLE)
we add an explicit specialisation for long
The recommendation is to use the link flag --no-undefined
and to fed *all* dependencies to the respective link step.
This changeset enables this strict linking of dependencies.
It turned out that our dependencies were already sane
(with the sole exception of a direct dependency to X-Lib
in the XV viewer widget)
- upgrade the configuration to a current version
- provide a frontpage with cross-links to other documentation
- define a set of modules; relevant classes and files can be
added to these, to create a exploration path for new readers
- fix a lot of errors in documentation comments
- use a custom configuration for the documentation pages
- tweak the navigation, the sections and further arrangements
to make them stand out more prominently, some entity comments
where started with a line of starts. Unfortunately, doxygen
(and javadoc) only recogise comments which are started exactly
with /**
This caused quite some comments to be ignored by doxygen.
Credits to Hendrik Boom for spotting this problem!
A workaround is to end the line of stars with *//**
We don't need this ability and it pushes us into using a
central registry. This solution turned out to be problematic
when loading dynamic libraries (plug-ins).
Clang doesn't allow to declare a private nested class as friend.
This is unfortunate, but likely correct to the letter of the standard.
As a workaround, now we're creating the instances within a static
function of DependencyFactory -- in the end this improves readability
A second issue fixed with this changeset is the scope of the
marker function. Clang is right, this isn't ADL, thus an inline
friend definition is simply not visible outside the class.
lib::Depend<TY> works as drop-in replacement for lib::Singleton<TY>
This changeset removes the convoluted special cases like
SingletonSub and MockInjector.
Clang seems to evaluate the terms of a function call in another order
than GCC -- this uncovered re-entrance errors in some metaprogramming tests,
where we re-used a global formatter object in recursive instantiations.
Clang is more insistent when it comes to enforcing 'protected' visibility.
Since in this case the basic design can be considered sane and optimal, the
only (and obvious) solution is to nest the PIMPL into a default base class
for implementation; this mirrors the structure of the interface.
Compilation with Clang 3.0 (which is available in Debian/stable) fails,
mostly due to some scoping and naming inconsistencies which weren't detected
by GCC. At some instances, Clang seems to have problems to figure out a
perfectly valid type definition; these can be resolved by more explicit
typing (which is preferrable anyway)
using our util::_Fmt front-end helps to reduce the code size,
since all usages rely on a single inclusion of boost::format
including boost::format via header can cause quite some code bloat
NOTE: partial solution, still some further includes to reorganise
