//+------------------------------------------------------------------+
//|                                                        Repro.mq5 |
//|                                   Copyright 2026, Niquel Mendoza |
//|                                             https://www.mql5.com |
//+------------------------------------------------------------------+
#property copyright "Copyright 2026, Niquel Mendoza"
#property link      "https://www.mql5.com"
#property version   "1.00"
#property strict

//+------------------------------------------------------------------+
//|                                                                  |
//+------------------------------------------------------------------+
typedef string(*FormatFunc)(double value, int8_t decimals);
string DefaultFormat(double value, int8_t decimals)
 {
  return DoubleToString(value, decimals);
 }
class CValue
 {
public:
                     CValue(void) {}
                    ~CValue(void) {}
  FormatFunc         m_func;
  void               Set(FormatFunc func_txt)  
   {
    m_func = func_txt == NULL ? DefaultFormat : func_txt;
   }
 };

//+------------------------------------------------------------------+
//| Script program start function                                    |
//+------------------------------------------------------------------+
void OnStart()
  {
//---
  CValue v;
  v.Set(DefaultFormat); 
  Print(v.m_func(10.0, 1));
  }
//+------------------------------------------------------------------+
/*
Repro.mq5			
Internal compiler error			
*/