- use allocator class to wrap the stream pointers instead of passing
them into ISstream, OSstream and using a dynamic cast to delete
then. This is especially important if we will have a bidirectional
stream (can't delete twice!).
STYLE:
- file stream constructors with std::string (C++11)
- for rewind, explicit about in|out direction. This is not currently
important, but avoids surprises with any future bidirectional access.
- combined string streams in StringStream.H header.
Similar to <sstream> include that has both input and output string
streams.
- inherit from std::iterator to obtain the full STL typedefs, meaning
that std::distance works and the following is now possible:
labelRange range(100, 1500);
scalarList list(range.begin(), range.end());
--
Note that this does not work (mismatched data-types):
scalarList list = identity(12345);
But this does, since the *iter promotes label to scalar:
labelList ident = identity(12345);
scalarList list(ident.begin(), ident.end());
It is however more than slightly wasteful to create a labelList
just for initializing a scalarList. An alternative could be a
a labelRange for the same purpose.
labelRange ident = labelRange::identity(12345);
scalarList list(ident.begin(), ident.end());
Or this
scalarList list
(
labelRange::null.begin(),
labelRange::identity(12345).end()
);
This uses a concept similar to what std::valarray and std::slice do.
A labelRange provides a convenient container for holding start/size
and lends itself to addressing 'sliced' views of lists.
For safety, the operations and constructors restricts the given input range
to a valid addressible region of the underlying list, while the labelRange
itself precludes negative sizes.
The SubList version is useful for patches or other things that have a
SubList as its parameter. Otherwise the UList [] operator will be the
more natural solution. The slices can be done with a labelRange, or
a {start,size} pair.
Examples,
labelList list1 = identity(20);
list1[labelRange(18,10)] = -1;
list1[{-20,25}] = -2;
list1[{1000,5}] = -3;
const labelList list2 = identity(20);
list2[{5,10}] = -3; // ERROR: cannot assign to const!
- Introduce writeList(Ostream&, label) method in various List classes to
provide more flexibility and avoid hard-coded limits when deciding if a
list is too long and should be broken up into multiple lines (ASCII only).
- The old hard-code limit (10) is retained in the operator<< versions
- This functionality is wrapped in the FlatOutput output adapter class
and directly accessible via the 'flatOutput()' function.
Eg,
#include "ListOps.H"
Info<< "methods: " << flatOutput(myLongList) << endl;
// OR
Info<< "methods: ";
myLongList.writeList(os) << endl;
Until C++ supports 'concepts' the only way to support construction from
two iterators is to provide a constructor of the form:
template<class InputIterator>
List(InputIterator first, InputIterator last);
which for some types conflicts with
//- Construct with given size and value for all elements
List(const label, const T&);
e.g. to construct a list of 5 scalars initialized to 0:
List<scalar> sl(5, 0);
causes a conflict because the initialization type is 'int' rather than
'scalar'. This conflict may be resolved by specifying the type of the
initialization value:
List<scalar> sl(5, scalar(0));
The new initializer list contructor provides a convenient and efficient alternative
to using 'IStringStream' to provide an initial list of values:
List<vector> list4(IStringStream("((0 1 2) (3 4 5) (6 7 8))")());
or
List<vector> list4
{
vector(0, 1, 2),
vector(3, 4, 5),
vector(6, 7, 8)
};
