Python - print string to screen, include \n in output

Question

I have the following code:

pattern = "something.*\n" #intended to be a regular expression

fileString = some/path/to/file

numMatches = len( re.findall(pattern, fileString, 0) )

print "Found ", numMatches, " matches to ", pattern, " in file."

I want the user to be able to see the '\n' included in pattern. At the moment, the '\n' in pattern writes a newline to the screen. So the output is like:

Found 10 matches to something.*
 in file.

and I want it to be:

Found 10 matches to something.*\n in file.

Yes, pattern.replace("\n", "\n") does work. But I want it to print all forms of escape characters, including \t, \e etc. Any help is appreciated.

Solution 1

Use repr(pattern) to print the \n the way you need.

Solution 2

Try this:

displayPattern = "something.*\\n"
print "Found ", numMatches, " matches to ", displayPattern, " in file."

You'll have to specify a different string for each case of the pattern - one for matching and one for displaying. In the display pattern, notice how the \ character is being escaped: \\.

Alternatively, use the built-in repr() function:

displayPattern = repr(pattern)
print "Found ", numMatches, " matches to ", displayPattern, " in file."

Comments

[dkroy]

This has already been asked, hopefully this points you in the correct direction: stackoverflow.com/questions/6477823/…

[abhishekgarg]

displayPattern = "something.*\s" use \s to find the newline character

[Nick Peterson]

Why use string.__repr__() instead of repr(string)?

[Drew]

@ntpeterson I didn't realize it existed until just now. Changing it now.