Q168377: PRB: STL string Class replace Function Does Not Work as Expected

Article: Q168377
Product(s): Microsoft C Compiler
Version(s): 4.2 5.0
Operating System(s): 
Keyword(s): kbVC420 kbVC500 kbVC600
Last Modified: 17-JUL-2001

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The information in this article applies to:

- The Standard C++ Library, included with:
   - Microsoft Visual C++, 32-bit Enterprise Edition, version 4.2 
   - Microsoft Visual C++, 32-bit Professional Edition, version 4.2 
   - Microsoft Visual C++, 32-bit Enterprise Edition, version 5.0 
   - Microsoft Visual C++, 32-bit Professional Edition, version 5.0 
   - Microsoft Visual C++, 32-bit Enterprise Edition, version 6.0 
   - Microsoft Visual C++, 32-bit Professional Edition, version 6.0 
   - Microsoft Visual C++, 32-bit Learning Edition, version 6.0 
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SYMPTOMS
========

The string::replace member function does not work as expected. This is because
the same string object is used for modification and input. Many data
manipulation routines do not check for overlapping or identical arguments,
causing unexpected results.

RESOLUTION
==========

Create a temporary copy of the string as shown below:

  s1.replace (1,2,string("c"));

STATUS
======

This behavior is by design.

MORE INFORMATION
================

Steps to Reproduce Behavior
---------------------------

The sample code below demonstrates the behavior reported in the SYMPTOMS
section.

  #include <iostream>
  #include <string>
  using namespace std ;
  void f1()
   {
    string s ("abcd");
    s.replace (1,2,s,2,1);
    cout << "s (should be 'acd'): " << s << endl << endl;
   }
  int main ()
   {
     f1();// prints "add" instead of "acd"
     return 0 ;
   }

Additional query words:

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Keywords          : kbVC420 kbVC500 kbVC600 
Technology        : kbVCsearch kbAudDeveloper kbVCLibrary
Version           : 4.2 5.0
Issue type        : kbprb

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