how to notify one class about the streamer for another?

Terrence Brannon (brannon@quake.usc.edu)
Tue, 17 Jun 1997 17:39:12 +0800


The #ifdef/#ifndef mods Fons sent me work just fine. Thanks a
million. I have no problem with rootcint now. Now I have some sort of
function prototyping problem because one class demands functionality
defined in another class:

rootcint paramVecDict.cc -c paramVec.h
Note: operator new() masked c
Note: operator delete() masked c
class paramVec in paramVec.h line 46 original base of virtual func
g++ -O -fPIC -I/oscar/public/root/include -c paramVecDict.cc -o paramVecDict.o
paramVecDict.cc: In method `void paramVec::Streamer(class TBuffer &)':
paramVecDict.cc:537: no match for `operator <<(class TBuffer, class param *)'
make: *** [paramVecDict.o] Error 1
brannon@surf ~/rs/VisionMagick/terry :

====
The reason this occurs is that the class paramVec has an object of
class param as a component. When the Streamer for class paramVec
attempts to write its "s" field which is of class param, it is
implicitly looking for an output operator of type param:

void paramVec::Streamer(TBuffer &R__b)
{
// Stream an object of class paramVec.

if (R__b.IsReading()) {
Version_t R__v = R__b.ReadVersion();
R__b >> len;
R__b >> s; // ******* <----- s is of type param ***************
} else {
R__b.WriteVersion(paramVec::IsA());
R__b << len;
R__b << s;
}
}

I have generated such an operator by successfully running rootcint on
the class param, generating paramDict.{cc,h}. However, there is
nothing in paramDict.h which "prototypes" the output operator, hence I
cant just include paramDict.h in paramVecDict.h. But I must have some
way of letting g++ know that there is indeed an output operator for
things of class param, it's just defined in a .cc file with no header.

1:How is this done?
2:Once I create the .o files and dictionaries for param.cc and
paramVec.cc, what do I need to do to get HTML out of them?

It's probably not necessary, but I include all the pertinent files:

============================== param.defs.h
// This may look like C code, but it is really -*- C++ -*-
/*
Copyright (C) 1988 Free Software Foundation
written by Doug Lea (dl@rocky.oswego.edu)

This file is part of the GNU C++ Library. This library is free
software; you can redistribute it and/or modify it under the terms of
the GNU Library General Public License as published by the Free
Software Foundation; either version 2 of the License, or (at your
option) any later version. This library is distributed in the hope
that it will be useful, but WITHOUT ANY WARRANTY; without even the
implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
PURPOSE. See the GNU Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with this library; if not, write to the Free Software
Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
*/


#ifndef _paramdefs_h
#define _paramdefs_h 1

#ifdef __CINT__
class String; // this is enough don't need to load all iostream.h
#else
#include <String.h>
#endif

#ifdef __CINT__
typedef void (*one_arg_error_handler_t)(const char*);
typedef void (*two_arg_error_handler_t)(const char*, const char*);
#endif
#include "Rtypes.h" // required for ClassDef

class param {
public:
ClassDef(param,1)
String name;
String val_strings[2]; /* current and default val strings */

int operator==(const param &p2) const {
return (name == p2.name);
}

};

// equality operator
#ifndef paramEQ
#define paramEQ(a, b) ((a) == (b))
#endif

// less-than-or-equal
#ifndef paramLE
#define paramLE(a, b) ((a) <= (b))
#endif

// comparison : less-than -> < 0; equal -> 0; greater-than -> > 0
#ifndef paramCMP
#define paramCMP(a, b) ( ((a) <= (b))? (((a) == (b))? 0 : -1) : 1 )
#endif

// hash function
#ifndef paramHASH
extern unsigned int hash(param&);
#define paramHASH(x) hash(x)
#endif

// initial capacity for structures requiring one

#ifndef DEFAULT_INITIAL_CAPACITY
#define DEFAULT_INITIAL_CAPACITY 100
#endif

// HASHTABLE_TOO_CROWDED(COUNT, SIZE) is true iff a hash table with COUNT
// elements and SIZE slots is too full, and should be resized.
// This is so if available space is less than 1/8.

#define HASHTABLE_TOO_CROWDED(COUNT, SIZE) ((SIZE) - ((SIZE) >> 3) <= (COUNT))

#endif

====================================== paramVec.h

// This may look like C code, but it is really -*- C++ -*-
/*
Copyright (C) 1988 Free Software Foundation
written by Doug Lea (dl@rocky.oswego.edu)

This file is part of the GNU C++ Library. This library is free
software; you can redistribute it and/or modify it under the terms of
the GNU Library General Public License as published by the Free
Software Foundation; either version 2 of the License, or (at your
option) any later version. This library is distributed in the hope
that it will be useful, but WITHOUT ANY WARRANTY; without even the
implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
PURPOSE. See the GNU Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with this library; if not, write to the Free Software
Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
*/

#ifndef _paramVec_h
#ifdef __GNUG__
#pragma interface
#endif
#define _paramVec_h 1

#ifndef __CINT__
#include <builtin.h>
#else
typedef void (*one_arg_error_handler_t)(const char*);
typedef void (*two_arg_error_handler_t)(const char*, const char*);
#endif
#include "param.defs.h"
#include "Rtypes.h" // required for ClassDef

#ifndef _param_typedefs
#define _param_typedefs 1
typedef void (*paramProcedure)(param&);
typedef param (*paramMapper)(param&);
typedef param (*paramCombiner)(param&, param&);
typedef int (*paramPredicate)(param&);
typedef int (*paramComparator)(param&, param&);
#endif

class paramVec
{
protected:
int len; // put comments here (will go in doc)
param *s; // idem...

paramVec(int l, param* d);
public:
ClassDef(paramVec,1)
paramVec ();
paramVec (int l);
paramVec (int l, param& fill_value);
paramVec (const paramVec&);
~paramVec ();

paramVec & operator = (const paramVec & a);
paramVec at(int from = 0, int n = -1);

int capacity() const;
void resize(int newlen);

param& operator [] (int n);
param& elem(int n);

friend paramVec concat(paramVec & a, paramVec & b);
friend paramVec map(paramMapper f, paramVec & a);
friend paramVec merge(paramVec & a, paramVec & b, paramComparator f);
friend paramVec combine(paramCombiner f, paramVec & a, paramVec & b);
friend paramVec reverse(paramVec & a);

void reverse();
void sort(paramComparator f);
void fill(param& val, int from = 0, int n = -1);

void apply(paramProcedure f);
param reduce(paramCombiner f, param& base);
int index(param& targ);

friend int operator == (paramVec& a, paramVec& b);
friend int operator != (paramVec& a, paramVec& b);

void error(const char* msg);
void range_error();
};

extern void default_paramVec_error_handler(const char*);
extern one_arg_error_handler_t paramVec_error_handler;

extern one_arg_error_handler_t
set_paramVec_error_handler(one_arg_error_handler_t f);

inline paramVec::paramVec()
{
len = 0; s = 0;
}

inline paramVec::paramVec(int l)
{
s = new param [len = l];
}

inline paramVec::paramVec(int l, param* d) :len(l), s(d) {}

inline paramVec::~paramVec()
{
delete [] s;
}

inline param& paramVec::operator [] (int n)
{
if ((unsigned)n >= (unsigned)len)
range_error();
return s[n];
}

inline param& paramVec::elem(int n)
{
return s[n];
}

inline int paramVec::capacity() const
{
return len;
}

inline int operator != (paramVec& a, paramVec& b)
{
return !(a == b);
}

#endif

======================================= root_makefile
#---------------------------------------------------
CXX = g++
CXXFLAGS = -O -fPIC -I$(ROOTSYS)/include
LD = g++
LDFLAGS = -g
SOFLAGS = -Wl,-soname,libEvent.so -shared
LIBS = $(ROOTLIBS) -lg++ -lm -ldl -rdynamic
GLIBS = $(ROOTLIBS) $(ROOTGLIBS) -L/usr/X11R6/lib -lXm -lXpm \
-lXt -lXext -lX11 -lg++ -lm -ldl -rdynamic

HDRS = paramVec.h

SRCS = small_main.cc paramVec.cc paramVecDict.cc paramDict.cc

OBJS = small_main.o paramVec.o paramVecDict.o paramDict.o

PROGRAM = myroot

all: clean $(PROGRAM)

$(PROGRAM): $(OBJS)
echo "Linking $(PROGRAM) ..."
$(LD) $(LDFLAGS) $(OBJS) $(LIBS) -o $(PROGRAM)
echo "done"

clean:;
rm -f $(OBJS) core *Dict.*

###
paramVec.o: paramVec.h

paramVecDict.cc: paramVec.h
echo "Generating dictionary ..."
rootcint paramVecDict.cc -c paramVec.h

paramDict.cc: param.defs.h
echo "Generating dictionary ..."
rootcint paramDict.cc -c param.defs.h
#---------------------------------------------------

================================= small_main.cc

//--------------------------------------------------
#include "TROOT.h"
#include "TRint.h"

int Error; //left undefined by Motif

extern void InitGui(); // initializer for GUI needed for interactive interface
VoidFuncPtr_t initfuncs[] = { InitGui, 0 };

// Initialize the ROOT system
TROOT root("Rint","The ROOT Interactive Interface", initfuncs);

int main(int argc, char **argv)
{
// Create interactive interface
TRint *theApp = new TRint("ROOT example", &argc, argv, NULL, 0);

// Run interactive interface
theApp->Run();

return(0);
}

-- 
o============o  Sending unsolicited commercial e-mail (UCE)  to this address
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o============o  minimum for professional proofreading & technical assessment.
  Terrence Brannon * brannon@quake.usc.edu * http://quake.usc.edu/~brannon