breaking up long path names

Question

I am having trouble breaking the path into two lines in my python compiler. It is simply a long path on the compiler screen and i have to stretch the window too wide. I know how to break a print("string") into two lines of code that will compile correctly, but not an open(path). As I write this I notice the text box can not even hold it all on one line. print()

`raw_StringFile = open(r'C:\Users\Public\Documents\year 2013\testfiles\test          code\rawstringfiles.txt', 'a')`

Very helpful tips for long path names here. I think the r prefix being used on multiple lines helped a lot. — Adreamer82, Oct 01 '13 at 22:00

George Mitchell · Accepted Answer · 2013-10-01T20:21:41.637

13

That is what the \ is for.

>>> mystr = "long" \
... "str"
>>> mystr
'longstr'

Or in your case:

longStr = r"C:\Users\Public\Documents\year 2013\testfiles" \
           r"\testcode\rawstringfiles.txt"
raw_StringFile = open(longStr, 'a')

EDIT

Well, you don't even need the \ if you use parenthesis, i.e.:

longStr = (r"C:\Users\Public\Documents\year 2013\testfiles"
               r"\testcode\rawstringfiles.txt")
raw_StringFile = open(longStr, 'a')

edited Oct 01 '13 at 20:21

answered Oct 01 '13 at 20:13

George Mitchell

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2

Using \ at the end of lines isn't PEP8ish – cmd Oct 01 '13 at 20:18
@cmd: Gah! C! It seeps through and poisons everything! – George Mitchell Oct 01 '13 at 20:19

score 7 · Answer 2 · answered Oct 01 '13 at 20:13

Python permits concatenating strings merely by placing them adjacently:

In [67]: 'abc''def'
Out[67]: 'abcdef'

In [68]: r'abc'r'def'
Out[68]: 'abcdef'

In [69]: (r'abc'
   ....: r'def')
Out[69]: 'abcdef'

So something like this ought to work for you.

raw_StringFile = open(r'C:\Users\Public\Documents\year 2013\testfiles'
                      r'\testcode\rawstringfiles.txt', 'a')

Another option is to use os.path.join:

myPath = os.path.join(r'C:\Users\Public\Documents\year 2013\testfiles',
                      r'testcode\rawstringfiles.txt')
raw_StringFile = open(myPath, 'a')

You cannot use a backslash as the last character in a raw string literal. — Martijn Pieters, Oct 01 '13 at 20:14

score 3 · Answer 3 · edited May 23 '17 at 12:34

You can place your string inside parenthesis, like this:

>>> (r'C:\Users\Public\Documents'
...  r'\year 2013\testfiles\test          code'
...  r'\rawstringfiles.txt')
'C:\\Users\\Public\\Documents\\year 2013\\testfiles\\test          code\\rawstringfiles.txt'

This is called "String literal concatenation". Quote from docs:

Multiple adjacent string literals (delimited by whitespace), possibly using different quoting conventions, are allowed, and their meaning is the same as their concatenation. Thus, "hello" 'world' is equivalent to "helloworld". This feature can be used to reduce the number of backslashes needed, to split long strings conveniently across long lines, or even to add comments to parts of strings, for example:
re.compile("[A-Za-z_]"       # letter or underscore
           "[A-Za-z0-9_]*"   # letter, digit or underscore
)

Also see:

RyPeck · Answer 4 · 2013-10-02T22:25:29.720

Python has a nifty feature called Implicit line joining.

Expressions in parentheses, square brackets or curly braces can be split over more than one physical line without using backslashes. For example:

month_names = ['Januari', 'Februari', 'Maart',      # These are the
               'April',   'Mei',      'Juni',       # Dutch names
               'Juli',    'Augustus', 'September',  # for the months
               'Oktober', 'November', 'December']   # of the year

So for your question -

raw_StringFile = open(r'C:\Users\Public\Documents\year 2013\testfiles'
                      r'\testcode\rawstringfiles.txt', 'a')

EDIT - In this example, it is actually String literal concatenation.

breaking up long path names

4 Answers4