Question

我第一次收到这个错误，我不太清楚这是什么意思。

这是我第一次玩try / catch。我知道我的格式非常混乱，我会记住下次组织它！

======= DRIVER ======

import subprocess

def winexists(target):
    for line in subprocess.check_output(['wmctrl', '-l']).splitlines():
        window_name = line.split(None, 3)[-1].decode()
        if window_name == target:
            return True
    return False

===== trashcan.cpp ======

 #include "trashcan.h"
 #include <iostream> 
 using namespace std;


int main( ) {
cout << "Welcome to TrashCan Program!" << endl;
TrashCan myCan;
TrashCan yourCan;
TrashCan nothing;

yourCan.setSize( 12 );
myCan.setSize( 12 );
nothing.setSize ( 0 );

yourCan.addItem( );
yourCan.addItem( );


myCan.addItem( );








myCan.printCan();
yourCan.printCan();

TrashCan combined = yourCan + myCan;
  cout << "this can's filled to " << combined.getContents( ) << endl;

TrashCan other = combined - myCan;
  cout << "the other can's filled to " << other.getContents( ) << endl;

if (combined > other) {
cout << "looks like combined is bigger..." << endl;
}
else {
cout << "looks like other is bigger..." << endl;
}
if (myCan > other) {
cout << "looks like myCan is bigger..." << endl;
}
else {
cout << "looks like other is bigger..." << endl;
}
if (yourCan < myCan) {
cout << "looks like yourCan is smaller..." << endl;
}
else {
cout << "looks like myCan is smaller..." << endl;
}

// let's throw some exceptions...

try {
TrashCan empty = empty - combined;
cout << "something not right here..." << endl;
} catch( std::logic_error ) {
// an exception should get thrown... 
// so the lines of code here should
// be run, not the cout statement above...
cout << "exception was caught.  moving on..." << endl;
}

try {
nothing.addItem( );
cout << "something not right here..." << endl;
} catch( std::logic_error ) {
// an exception should get thrown... 
// so the lines of code here should
// be run, not the cout statement above...
cout << "exception was caught.  moving on..." << endl;

}


return( 0 );
}

== HEADER ======

#include "trashcan.h"
#include <iostream>
#include <cstdlib>

using namespace std;



TrashCan::TrashCan( ) {
myIsCovered = false;
my_Size = 0;
my_Contents = 0;
my_Empty = 0;
}

TrashCan::TrashCan( int size ) {
myIsCovered = false;
my_Size = size;
my_Contents = 0;
my_Empty = 0;
}

TrashCan::TrashCan( int size, int contents, int empty ) {
myIsCovered = false;
my_Size = size;
my_Contents = contents;
my_Empty = empty;
}

void TrashCan::setSize( int size ) {
if (size < 0 ){
    throw logic_error("exception was caught.  moving on...");
}
else{
my_Size = size;
}
}

int TrashCan::getSize( ) {
return( my_Size );

}

int TrashCan::getContents( ) {
return( my_Contents );
}

void TrashCan::addItem( ) {
my_Contents = my_Contents + 1;
if (my_Contents > my_Size || my_Contents < my_Size){
    throw logic_error("exception was caught.  moving on...");
}
}

void TrashCan::empties( ) {
my_Contents = 0;
}

void TrashCan::cover( ) {
myIsCovered = true;
}

void TrashCan::uncover( ) {
myIsCovered = false;
}

void TrashCan::printCan( ) {
cout << "A TrashCan with a size=" << my_Size << " and containing " <<                     my_Contents << " piece";
if (my_Contents != 1) {
    cout << "s";
}
cout << " of trash" << endl;
}

TrashCan operator+ ( const TrashCan& yourCan, const TrashCan& myCan ) {             /* This is where I override the + and - operators... I put in the error messages     for over filling and under filling the trashcan */

    TrashCan combined;
combined.my_Contents = yourCan.my_Contents + myCan.my_Contents ;


    return( combined );

}

TrashCan operator- ( const TrashCan& combined, const TrashCan& myCan ){
TrashCan other;
TrashCan empty;
empty.my_Contents = -1;

if ( empty.my_Contents < 0 ){
    throw logic_error("exception was caught.  moving on...");
}
else
{
other.my_Contents = combined.my_Contents - myCan.my_Contents;
return (other );
}
}

bool operator> ( const TrashCan& myCan, const TrashCan& yourCan) {                      /* MY bool override for the '< and > '  operators. */
TrashCan combined;
combined.my_Contents = yourCan.my_Contents + myCan.my_Contents ;

TrashCan empty;
empty.my_Empty = 0;


TrashCan other;
other.my_Contents = combined.my_Contents - myCan.my_Contents;


 return combined.my_Contents > other.my_Contents && myCan.my_Contents >     other.my_Contents; 



}

bool operator< (const TrashCan& myCan, const TrashCan& yourCan ) {          
TrashCan combined;
combined.my_Contents = yourCan.my_Contents + myCan.my_Contents ;

TrashCan other;
other.my_Contents = combined.my_Contents - myCan.my_Contents;

if (yourCan.my_Contents < myCan.my_Contents ){
    return yourCan.my_Contents > myCan.my_Contents ; }
else {
    return yourCan.my_Contents < myCan.my_Contents;
}





}


ostream& operator<< (ostream &out, TrashCan& myCan)
{
out <<myCan.my_Contents << " Contents in this trashcan";
return out;
}

Answer 1

一个问题是：

void TrashCan::addItem() {
    my_Contents = my_Contents + 1;
    if (my_Contents > my_Size || my_Contents < my_Size) {
        throw logic_error("exception was caught.  moving on...");
    }
}

您正在抛出logic_error例外，但您的main函数无法捕获错误。因此，您的程序终止。

我不知道此代码的意图，但如果您只是简单地运行它，每次调用my_Contents < my_Size时都会看到add_Item，从而导致异常抛出。

为什么不发信息让自己说服出错？

void TrashCan::addItem() {
    my_Contents = my_Contents + 1;
    if (my_Contents > my_Size || my_Contents < my_Size) 
    {
        std::cout << "oh no, I'm about to die..." << std::endl;
        throw logic_error("exception was caught.  moving on...");
    }
}

然后，您的main功能，如果您不希望以未处理的例外结束，则必须执行try / catch：

try { 
   yourCan.addItem();
}
catch(logic_error& e) { /* whatever */ }

调试错误r6010 Abort已在C ++中调用

1 个答案: