Không có vấn đề mà Giám đốc điều hành Starbuzz là, nếu anh ta có di động của mình gần đó, ông nhận được tin vẫn có thể gọi chức năng Twitter như thế này: send_to_ twitter ()? Hay tôi luôn luôn phải cung cấp một giá trị cho tham số msg?Không tất cả những tùy chọn kinda khó hiểu? | modular programming A late night email ruins your day A few days after the demo you get a late night email from the friend who wrote the second program based on your code Hi sort things out. See you in the morning Something really strange has happened. Even though your code used to work it has suddenly started to go wrong. Meanwhile your friend s program which is really just a modified copy of your program is working perfectly. Looks like you better get to the health club bright and early tomorrow morning and see what s happened. you are here 4 187 pricey donut 50 000. for a donut When you arrive at the health club you find out exactly what s happened. The entire day s sales have been rejected by the bank for two reasons s The credit card numbers are all fake invalid. The bank was really worried about this one because they think someone must have hacked into the system to generate the messed-up credit card numbers. The prices are ridiculous. One of the recorded sales was for a donut that cost over 50 000 And what makes it worse this was the first time we sent the transaction file to our new bank We only switched over the day before yesterday so that I could secure a loan for the new weight room This looks like a really serious problem. Let s take a look at the file that the bank rejected. 188 Chapter 6 modular programming Only the sales from your program were rejected The transactions . txt file that was sent to the bank contains all of the day s sales from both your POS program in the coffee bar and your friend s POS program in the gym. This is a section of the file As expected each record from each of the POS programs has been appended to the transactions file. That bit appears to be working fine. But something is not quite right here. Study the two records carefully. Is there a difference between them that might explain why one was accepted and the other was rejected Think about recent events. What do you think has caused this problem you are here 4 .
