Problem compiling with TPRegexp

[aharel]

Hello,

I’m having a hard time compiling code that uses TString::Index( TPRegExp, … ). The error message complains, well, see for yourself:

/mnt/data/cms/macros/./testP.c: In function ‘void testP()’:
/mnt/data/cms/macros/./testP.c:14: error: no matching function for call to ‘TString::Index(TPRegexp, int)’
/mnt/data/downloads/root/include/TString.h:510: note: candidates are: Ssiz_t TString::Index(const char*, Ssiz_t, TString::ECaseCompare) const
…
/mnt/data/downloads/root/include/TString.h:331: note: Ssiz_t TString::Index(const TRegexp&, Ssiz_t) const
/mnt/data/downloads/root/include/TString.h:332: note: Ssiz_t TString::Index(const TRegexp&, Ssiz_t*, Ssiz_t) const
/mnt/data/downloads/root/include/TString.h:333: note: Ssiz_t TString::Index(TPRegexp&, Ssiz_t) const
/mnt/data/downloads/root/include/TString.h:334: note: Ssiz_t TString::Index(TPRegexp&, Ssiz_t*, Ssiz_t) const

The program is simply (in a file called testP.c):

#include
#include “TROOT.h”
#include “TRegexp.h”
#include “TPRegexp.h”

using std::endl;
using std::cout;
using std::cerr;

void testP ()
{
TString ss;
ss.Index( TRegexp (“,”), Ssiz_t( 0 ) );
ss.Index( TPRegexp(“,”), Ssiz_t( 0 ) );
}

What am I missing?

[brun]

What you do is wrong. TString::Index expects an argument passed by reference, not by value. Change your code to

TString ss; TRegexp rex(","); ss.Index( rex, Ssiz_t( 0 ) ); ss.Index( rex, Ssiz_t( 0 ) );
Rene

[aharel]

Thanks Rene,

I forgot that the compilers protect against using temporary variables for a non-const pass by reference. I think it used to yield only a warning message when I learnt C++

But in this case, this is a mild interface bug - TString::Index should accept a const TPRegexp. I guess there’s something tricky in the implementation (I see it neither in TString.h, nor in TString.cxx), but I’m sure this is fixable.

Cheers,
Amnon