从 Pascal 过程中完全退出程序

Question

我的 Pascal 程序在主 begin语句和 4 个程序中有一个菜单。在每个程序中，我都会向用户确认他们是否要返回菜单，否则程序将退出，但是每次程序要退出时，它都会再次返回菜单。

procedure quit;
begin
  writeln('<Enter> to quit...');
  readln;
end

procedure error;
begin
  writeln('Error. Try Again...');
  readln;
end;

procedure option1;
begin
  clrscr;
  writeln('this is option 1');
  writeln('would you like to continue? (y/n)');
  readln(confirm);
  if confirm = 'y' then
  begin 
    writeln('something will happen...');
  end;

  if confirm = 'n' then
    begin
      writeln('Return to main menu ? (y/n)');
      readln(option);
      if option = 'y' then
        exit
      else
        quit;
    end;  
end;

procedure option2;
begin
  clrscr; 
  writeln('this is option2');
  writeln('would you like to continue? (y/n)');
  readln(confirm);
  if confirm = 'y' then
  begin 
    writeln('something will happen...');
  end;

  if confirm = 'n' then
    begin
      writeln('Return to main menu ? (y/n)');
      readln(option);
      if option = 'y' then
        exit
      else
        quit;
    end; 
end;

主要开始语句：

begin
  repeat
    1: clrscr;
    writeln('Pascal Menu');
    gotoxy(4, 3);
    writeln('1. Option 1');
    gotoxy(4, 4);
    writeln('2. Option 2');
    gotoxy(4, 5);
    writeln('0. Quit Program');
    readln(choice);

    if choice > 2 then
    begin
      error
    end;

  case choice of
    1: option1;
    2: option2;
    0: quit;
  end;
  until choice = 0;

  exit;           
end.

我对 Pascal 比较陌生，任何帮助将不胜感激。

Answer 1

调用halt传递所需的退出代码：

halt(0);

如果省略退出代码，则使用默认值0：

halt;