8.9. Debugging¶
When you are reading and writing files, you might run into problems with whitespace. These errors can be hard to debug because spaces, tabs, and newlines are normally invisible:
Before you keep reading...
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The built-in function repr
can help. It takes any object as
an argument and returns a string representation of the object. For
strings, it represents whitespace characters with backslash sequences:
This can be helpful for debugging.
One other problem you might run into is that different systems use
different characters to indicate the end of a line. Some systems use a
newline, represented \n
. Others use a return character, represented
\r
. Some use both. If you move files between different systems, these
inconsistencies might cause problems.
- \n
- This is the symbol for a newline.
- \t
- This is the symbol for a tab.
- \r
- This is the symbol for the return character.
- \'
- This is the symbol for the ' character in a string.
Q-4: Which of the following symbols create newlines, or returns, in files? Select all that apply.
For most systems, there are applications to convert from one format to another. You can find them (and read more about this issue) at wikipedia.org/wiki/Newline. Or, of course, you could write one yourself.