The subnet calculator helps you design networks by taking an IP address and network mask and returning information such as network, broadcast address, and host range.
One of a set of tools we're offering as a way of saying thank you for being a part of the community.
Course Of The Month
9 days, 10 hours left to enrollBecome a Premium Member and unlock a new, free course in leading technologies each month.
Solved
File window character eating
Posted on 1999-01-18
I'm trying to get into Pascal and I'm having some trouble understanding the file window.
1/ I want to skip leading non-digits from an input stream and I have the following code
read (c);
while not c in ['0'..'9'] do read (c);
This isn't working, properly, I'm not processing all the characters it seems. I'm not sure how to rewrite that loop using the input window. I think I must need it because I think my read statement is going too far.
2/ I'm trying to use the file window to slip blanks, like so
while input^ <> ' ' do read (c);
This sometimes crashes. What am I doing wrong?
1/ I want to skip leading non-digits from an input stream and I have the following code
read (c);
while not c in ['0'..'9'] do read (c);
This isn't working, properly, I'm not processing all the characters it seems. I'm not sure how to rewrite that loop using the input window. I think I must need it because I think my read statement is going too far.
2/ I'm trying to use the file window to slip blanks, like so
while input^ <> ' ' do read (c);
This sometimes crashes. What am I doing wrong?
[X]
Welcome to Experts Exchange
Add your voice to the tech community where 5M+ people just like you are talking about what matters.
- Help others & share knowledge
- Earn cash & points
- Learn & ask questions
2 Comments
1/ You're right, your input goes too far because when you stop reading, you've already given c the first digit of the number. You do need to use the file window as you suspected, like this -
while not (input^ in ['0' .. '9'] do
read (c);
2/ I expect your code crashes on empty files, or if the file is padded with blanks - because you will try to read past the end of the file.
Try this routine -
Finished := False;
repeat
if eof then
Finished := True
else if input^ = ' ' then
read (c)
else
Finished := True
until Finished;
This is a bit more complicated, but more robust !
Were these perhaps homework questions? They actually are examples from a Pascal book called 'Oh, Pascal' ! That takes me back to COMP101 ....
while not (input^ in ['0' .. '9'] do
read (c);
2/ I expect your code crashes on empty files, or if the file is padded with blanks - because you will try to read past the end of the file.
Try this routine -
Finished := False;
repeat
if eof then
Finished := True
else if input^ = ' ' then
read (c)
else
Finished := True
until Finished;
This is a bit more complicated, but more robust !
Were these perhaps homework questions? They actually are examples from a Pascal book called 'Oh, Pascal' ! That takes me back to COMP101 ....
Featured Post
Question has a verified solution.
If you are experiencing a similar issue, please ask a related question
Suggested Solutions
| Title | # Comments | Views | Activity |
|---|---|---|---|
| MAPI Error1: User cancelled request ? | 7 | 1,228 | |
| Real time Change DisplayName of service | 7 | 624 | |
| Lazarus (freePascal) DB Project Assistance | 14 | 495 | |
| Get notified when a TPopupMenu closes? | 4 | 178 |
I took on this little project as a proof of concept for IoT devices. My main goals were to find the easiest, cheapest way to stream data to the cloud. This article describes how to stream telemetry data to ThingSpeak via REST API. This can also be d…
Changing a few Outlook Options can help keep you organized!
Are you ready to implement Active Directory best practices without reading 300+ pages?
You're in luck. In this webinar hosted by Skyport Systems, you gain insight into Microsoft's latest comprehensive guide, with tips on the best and easiest way…
This video shows how to use Hyena, from SystemTools Software, to update 100 user accounts from an external text file. View in 1080p for best video quality.
Suggested Courses
Course of the Month9 days, 10 hours left to enroll
740 members asked questions and received personalized solutions in the past 7 days.
Join the community of 500,000 technology professionals and ask your questions.