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Fwd:constexpr w/c++ stdlib features??



I'm trying to convert various 'C'-isms in my code.

I had something that "passed" the "constexpr-test",
namely, constexpr const char ** cpu_states_txt = {"USR", "Ni", "Sys"...};

This compiled and worked just fine.  But I am trying to change it
to a vector or valarray:

constexpr const vector<const char *> const cpu_states_txt ={"Usr, "...."};

But I get:
g++: COMPILE linux/cpumeter.cc
linux/cpumeter.cc:272:56: error: the type âconst std::vector<const char*>â of constexpr variable âcpu_states_txtâ is not literal
            "HI","SI","STL","GST","NGS", "INT","USED");
                                                     ^
In file included from /usr/include/c++/4.8/vector:64:0,
              from ./fieldmetergraph.h:11,
              from linux/cpumeter.h:10,
              from linux/cpumeter.cc:7:
/usr/include/c++/4.8/bits/stl_vector.h:210:11: note: âstd::vector<const char*>â is not literal because:
  class vector : protected _Vector_base<_Tp, _Alloc>
        ^
/usr/include/c++/4.8/bits/stl_vector.h:210:11: note: âstd::vector<const char*>â has a non-trivial destructor linux/cpumeter.cc:272:56: error: conversion from âconst char [5]â to non-scalar type âconst std::vector<const char*>â requested
            "HI","SI","STL","GST","NGS", "INT","USED");
---------------------

It seems to be complaining about trying to express this 'constant' in terms of
a differnt constant.  Ok...fine... so how would I do it otherwise.

I tried () and {} for init-list, and types vector, valarray and array... Array was very disappointing in that it had no way to do something that was trivial in 'C' -- take it's size from the initializer list. ARG! How could someone create something so worthless. How would you ever get the index and the list automatically tied to coordinate w/each other. Anyway, vector and valarray both fail w/similar messages,

So I hate the idea of just leaving it as 'C', as I've noted the increase in
"power-tools" available to me if I use C++ (like xxx.sum() among others). Is
this something not possible in C++, or is it something g++ doesn't handle?

**Could** it handle it? I.e. is it within the scope of the std-lib and within the standard (don't know C++ very well -- especially the revised versions( last I
used C++ was in V1.0 that had no stdlib...)...

If it is something the lib 'could' (or should) handle, should I submit it
as a RFE or is it a bug?

Thanks much!
Linda







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