Ichthyostega
22b934673f
indicates rather questionable behaviour. The standard demands a templated static field to be defined before first odr-use. IIRC, it even demands a static field to be initialised prior to use in a ctor. But here the definition of the templated static member field is dropped off even after the definition of another static field, which uses the (templated) Front-end-class in its initialiser.
130 lines
3.7 KiB
C++
130 lines
3.7 KiB
C++
/* try.cpp - for trying out some language features....
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* scons will create the binary bin/try
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*
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*/
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// 8/07 - how to control NOBUG??
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// execute with NOBUG_LOG='ttt:TRACE' bin/try
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// 1/08 - working out a static initialisation problem for Visitor (Tag creation)
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// 1/08 - check 64bit longs
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// 4/08 - comparison operators on shared_ptr<Asset>
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// 4/08 - conversions on the value_type used for boost::any
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// 5/08 - how to guard a downcasting access, so it is compiled in only if the involved types are convertible
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// 7/08 - combining partial specialisation and subclasses
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// 10/8 - abusing the STL containers to hold noncopyable values
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// 6/09 - investigating how to build a mixin template providing an operator bool()
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// 12/9 - tracking down a strange "warning: type qualifiers ignored on function return type"
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// 1/10 - can we determine at compile time the presence of a certain function (for duck-typing)?
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// 4/10 - pretty printing STL containers with python enabled GDB?
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// 1/11 - exploring numeric limits
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// 1/11 - integer floor and wrap operation(s)
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// 1/11 - how to fetch the path of the own executable -- at least under Linux?
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// 10/11 - simple demo using a pointer and a struct
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// 11/11 - using the boost random number generator(s)
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// 12/11 - how to detect if string conversion is possible?
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// 1/12 - is partial application of member functions possible?
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// 5/14 - c++11 transition: detect empty function object
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// 7/14 - c++11 transition: std hash function vs. boost hash
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// 9/14 - variadic templates and perfect forwarding
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// 11/14 - pointer to member functions and name mangling
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// 8/15 - Segfault when loading into GDB (on Debian/Jessie 64bit
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// 8/15 - generalising the Variant::Visitor
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// 1/16 - generic to-string conversion for ostream
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// 1/16 - build tuple from runtime-typed variant container
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// 3/17 - generic function signature traits, including support for Lambdas
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// 9/17 - manipulate variadic templates to treat varargs in several chunks
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// 11/17 - metaprogramming to detect the presence of extension points
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// 11/17 - detect generic lambda
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// 12/17 - investigate SFINAE failure. Reason was indirect use while in template instantiation
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// 03/18 - Dependency Injection / Singleton initialisation / double checked locking
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// 04/18 - investigate construction of static template members
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/** @file try.cpp
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* Investigation: static initialisation order -- especially of static template member fields
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*/
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typedef unsigned int uint;
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#include "lib/format-cout.hpp"
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#include "lib/test/test-helper.hpp"
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#define SHOW_TYPE(_TY_) \
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cout << "typeof( " << STRINGIFY(_TY_) << " )= " << lib::meta::typeStr<_TY_>() <<endl;
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#define SHOW_EXPR(_XX_) \
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cout << "Probe " << STRINGIFY(_XX_) << " ? = " << _XX_ <<endl;
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template<typename T>
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class Factory
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{
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public:
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T val;
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Factory()
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: val{}
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{
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cout << "Factory-ctor val="<<val<<endl;
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}
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};
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template<typename T>
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class Front
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{
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public:
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static Factory<T> fac;
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Front()
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{
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cout << "Front-ctor val="<<fac.val<<endl;
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fac.val += 100;
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}
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T&
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operate ()
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{
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cout << "Front-operate val="<<fac.val<<endl;
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++ fac.val;
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return fac.val;
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}
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};
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template<typename T>
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Factory<T> Front<T>::fac;
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namespace {
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Front<int> front;
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int
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staticFun()
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{
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cout << "staticFun"<<endl;
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return front.operate() += 10;
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}
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int global_int = front.operate();
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}
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int
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main (int, char**)
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{
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cout << "make-Front<int>..."<<endl;
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Front<int> fint;
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int& i = fint.operate();
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cout << "main: val="<<i<<endl;
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cout << "main: staticFun..."<<staticFun()<<endl;
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cout << "global_int.......="<<global_int<<endl;
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cout << "\n.gulp.\n";
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return 0;
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}
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