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Reference Guide
TListAndSTL.C File Reference

Detailed Description

View in nbviewer Open in SWAN This is an example of using TList with STL algoritms in CLING.

Output produced by .x TListAndSTL.C

Value: test string #0
Value: test string #1
Value: test string #2
Value: test string #3
Value: test string #4
Value: test string #5
Value: test string #6
Value: test string #7
Value: test string #8
Value: test string #9
The string has been found: test string #4

TListAndSTL.C code

// STD
#include <algorithm>
#include <iostream>
#include <sstream>
// ROOT
#include "TList.h"
#include "TCollection.h"
#include "TObjString.h"
// A functor for the for_each algorithm
struct SEnumFunctor {
bool operator()(TObject *aObj) {
if (!aObj)
return false;
TObjString *str(dynamic_cast<TObjString*>(aObj));
if (!str)
return false;
cout << "Value: " << str->String().Data() << endl;
return true;
}
};
// A functor for the find_if algorithm
struct SFind {
// using this ugly constructor, since there is problems with std::bindX in CINT
SFind(const TString &aStr): fToFind(aStr) {
}
bool operator()(TObject *aObj) {
TObjString *str(dynamic_cast<TObjString*>(aObj));
return !str->String().CompareTo(fToFind);
}
private:
const TString fToFind;
};
// The "main" function
void TListAndSTL()
{
const Int_t size(10);
// Initializing TList container
TList stringList;
ostringstream ss;
for (int i = 0; i < size; ++i) {
ss << "test string #" << i;
TObjString *s(new TObjString(ss.str().c_str()));
stringList.Add(s);
ss.str("");
}
// ### Example #1
// Running the std::for_each algorithm on the list
for_each(stringList.begin(), stringList.end(), SEnumFunctor());
// ### Example #2
// We can try to find something in the container
// using the std::find_if algorithm on the list
string strToFind("test string #4");
SFind func(strToFind.c_str());
TIterCategory<TList> iter_cat(&stringList);
= find_if(iter_cat.Begin(), TIterCategory<TList>::End(), func);
// Checking the result
if (!(*found)) {
cerr << "Can't find the string: \"" << strToFind << "\" in the container" << endl;
return;
}
TObjString *str(dynamic_cast<TObjString*>(*found));
if (!str) {
cerr << "Can't find the string: \"" << strToFind << "\" in the container" << endl;
return;
}
cout << "The string has been found: " << str->String().Data() << endl;
}
int Int_t
Definition: CPyCppyy.h:43
size_t size(const MatrixT &matrix)
retrieve the size of a square matrix
TRObject operator()(const T1 &t1) const
TIter end() const
Definition: TCollection.h:291
TIter begin() const
Definition: TCollection.h:290
A doubly linked list.
Definition: TList.h:44
virtual void Add(TObject *obj)
Definition: TList.h:87
Collectable string class.
Definition: TObjString.h:28
Mother of all ROOT objects.
Definition: TObject.h:37
Basic string class.
Definition: TString.h:136
static constexpr double s
Author
Anar Manafov

Definition in file TListAndSTL.C.