lumiera_/research/try.cpp
2015-08-16 01:16:20 +02:00

113 lines
3.4 KiB
C++

/* try.cpp - for trying out some language features....
* scons will create the binary bin/try
*
*/
// 8/07 - how to control NOBUG??
// execute with NOBUG_LOG='ttt:TRACE' bin/try
// 1/08 - working out a static initialisation problem for Visitor (Tag creation)
// 1/08 - check 64bit longs
// 4/08 - comparison operators on shared_ptr<Asset>
// 4/08 - conversions on the value_type used for boost::any
// 5/08 - how to guard a downcasting access, so it is compiled in only if the involved types are convertible
// 7/08 - combining partial specialisation and subclasses
// 10/8 - abusing the STL containers to hold noncopyable values
// 6/09 - investigating how to build a mixin template providing an operator bool()
// 12/9 - tracking down a strange "warning: type qualifiers ignored on function return type"
// 1/10 - can we determine at compile time the presence of a certain function (for duck-typing)?
// 4/10 - pretty printing STL containers with python enabled GDB?
// 1/11 - exploring numeric limits
// 1/11 - integer floor and wrap operation(s)
// 1/11 - how to fetch the path of the own executable -- at least under Linux?
// 10/11 - simple demo using a pointer and a struct
// 11/11 - using the boost random number generator(s)
// 12/11 - how to detect if string conversion is possible?
// 1/12 - is partial application of member functions possible?
// 5/14 - c++11 transition: detect empty function object
// 7/14 - c++11 transition: std hash function vs. boost hash
// 9/14 - variadic templates and perfect forwarding
// 11/14 - pointer to member functions and name mangling
// 8/15 - Segfault when loading into GDB (on Debian/Jessie 64bit
/** @file try.cpp
** Investigation: Segfault when loading into GDB (on Debian/Jessie 64bit)
**
*/
#include "lib/test/test-helper.hpp"
//#include "lib/format-util.hpp"
#include "lib/meta/trait.hpp"
#include "lib/itertools.hpp"
#include "lib/symbol.hpp"
#include <iostream>
#include <string>
#include <vector>
using std::string;
using std::vector;
using std::cout;
using std::endl;
namespace { // helper to build range iterator on demand
template<class CON, typename TOGGLE = void>
struct _RangeIter
{
using StlIter = typename CON::const_iterator;
lib::RangeIter<StlIter> iter;
_RangeIter(CON const& collection)
: iter(begin(collection), end(collection))
{ }
};
}
template<class CON>
inline string
join (CON&& coll, string const& delim =", ")
{
using Coll = typename lib::meta::Strip<CON>::Type;
using Val = typename Coll::value_type;
std::function<string(Val const&)> toString = [] (Val const& val) { return string(val); };
_RangeIter<Coll> range(std::forward<Coll>(coll));
auto strings = lib::transformIterator(range.iter, toString);
if (!strings) return "";
std::ostringstream buffer;
for (string const& elm : strings)
buffer << elm << delim;
// chop off last delimiter
size_t len = buffer.str().length();
ASSERT (len > delim.length());
return buffer.str().substr(0, len - delim.length());
}
int
main (int, char**)
{
vector<string> crew;
crew.push_back("Picard");
crew.push_back("Riker");
crew.push_back("Data");
crew.push_back("Troi");
crew.push_back("Worf");
crew.push_back("Crusher");
crew.push_back("La Forge");
cout << "enterprise = " << join(crew)<<endl;
cout << "\n.gulp.\n";
return 0;
}