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问题[runtime]

Martin Hope
Direct
Asked: 2022-09-04 03:29:37 +0000 UTC
  • 0

有一个代码：

try:
    def f():
        print('hi')
        print('bye) # здесь намеренно пропущен закрывающий апостроф
except:
    pass
          
f()

实验的目的是找出当函数f的逐行定义（def）在运行时失败时调用函数时会发生什么。假设定义 (def) 作为语句失败，因此f不会在模块的全局范围内创建函数对象和对它的引用。因此，假设调用f()将导致引发 NameError。

事实上，事实证明在启动时抛出了一个 SyntaxError，并且没有打印 'hi' 行。我认为要么是blocktry没有捕捉到异常，要么是整个模块的bit-code无法创建，因此原则上没有启动，操作员def甚至都没有开始工作（实际上，就像随后的调用一样运算符f()）。

问题：请帮我弄清楚为什么电话f()打不通。也许我上面的一个假设是正确的，在这种情况下，我希望看到文档的链接详细解释正在发生的事情。

python runtime
Martin Hope
Ростислав Юшкевич
Asked: 2020-04-08 03:19:37 +0000 UTC
  • 1

运行时检查失败 #2 - 变量“编号”周围的堆栈已损坏。我不明白错误可能发生在哪里：我正在用 C 编写一个列表。结果，指针将 NULL 返回给 print 函数，因此不会打印列表。提前致谢

#include <iostream>
#include <string.h>

struct avia
{
    int number;
    float time;
    char destination;
    avia* next;
};
void instructions();
void createlist(avia* pbegin);
void insert(avia** elem, int number, float time, char destination);
int deleteelem(avia** elem, int number);
void printlist(avia* current);
void deletelist(avia* current);
int isempty(avia* elem);
int main()
{
    avia* head=NULL;
    int number;
    int choice;
    float time;
    char destination;
    instructions();
    scanf_s("%d", &choice);
    while (choice != 6)
    {
        switch (choice)
        {
        case 1:
            createlist(head);
            break;
        case 2:
            printf("Enter a number: \n");
            scanf_s("%d", &number);
            printf("Enter time:\n");
            scanf_s("%f", &time);
            printf("Enter destination:\n");
            scanf_s("%s", &destination, 30);
            insert(&head, number, time, destination);
            printlist(head);
            break;
        case 3:
            if (!isempty(head))
            {
                printf("Enter a number you want to delete\n");
                scanf_s("%d", &number);
                if (deleteelem(&head, number))
                {
                    printf("Object deleted");
                    printlist(head);
                }
                else
                {
                    printf("Number not found");
                }
            }
            else
            {
                printf("The list is empty\n");
            }
            break;
        case 4:
            if (!isempty(head))
            {
                deletelist(head);
            }
            else
            {
                printf("The list is empty\n");
            }
            break;
        case 5:
            if (!isempty(head))
            {
                printlist(head);
            }
            else
            {
                printf("The list is empty\n");
            }
            break;
        default:
            printf("Invalid choice\n");
            instructions();
            break;
        }
        printf("?\n");
        scanf_s("%d", &choice);
    }
    printf("End of run\n");
    return 0;
}
void instructions()
{
    printf("Enter choice:\n1 create an empty list\n 2 insert an element into the list.\n3 delete an element from the list. \n 4 delete the whole list\n 5 print the list\n 6 end program. \n");
}
void createlist(avia* elem)
{
    elem = NULL;
}
void insert(avia** elem, int number, float time, char destination)
{
    avia* newelem;
    newelem = (avia*)malloc(sizeof(avia)); 
    if (newelem != NULL)
    {
        newelem->number = number;
        newelem->time = time;
        newelem->destination = destination;
        newelem->next = NULL;
    }
    else printf("List not inserted. No memory available\n");
}
int deleteelem(avia** elem, int number)
{
    avia* previous;
    avia* current;
    avia* temp;
    if (number == (*elem)->number)
    {
        temp = *elem;
        *elem = (*elem)->next;
        free(temp);
        return(number);
    }
    else
    {
        previous = *elem;
        current = (*elem)->next;
        while (current != NULL && current->number != number)
        {
            previous = current;
            current = current->next;
        }
        if (current != NULL)
        {
            temp = current;
            previous = current->next;
            free(temp);
            return(number);
        }
    }
}
void printlist(avia* current)
{
    if (current == NULL)
    {
        printf("The list is empty\n");
    }
    else
    {
        printf("The list is: ");
        while (current != NULL)
        {
            printf("%d, %f, %s ->", current->number, current->time, current->destination);
            current = current->next;
        }
        printf("NULL");
    }
}
void deletelist(avia* current)
{
    avia* temp;
    if (current == NULL)
    {
        printf("The list is empty\n");
    }
    else
    {
        while (current != NULL)
        {
            temp = current;
            current = current->next;
            free(temp);
        }
    }
}
int isempty(avia* elem)
{
    return elem == NULL;
}
runtime