Python code for replacing texts not working

Question

My code is this.

import fileinput
for line in fileinput.FileInput("aaaa.txt",inplace=1):
     map_dict = {'\N':'999999999', '[':'(', '＆':'&'}
     line = ''.join(map_dict.get(c,c) for c in line)
     print line,

I experimented this with aaaa.txt but it's simply not replacing anything.

A simpler code that I know works is

import fileinput
for line in fileinput.FileInput("aaaa.txt",inplace=1):
    line = line.replace("\N","999999999")
    print line,

But I want to make the first code work, because it replaces multiple things.

refer to this http://stackoverflow.com/questions/2484156/is-str-replace-replace-ad-nauseam-a-standard-idiom-in-python — shifu, Jun 25 '14 at 15:34

score 2 · Accepted Answer · answered Jun 25 '14 at 15:30

2

\N is two character string. (same as '\\N')

>>> '\N'
'\\N'
>>> len('\N')
2

But iterating a string yields single character strings.

>>> for ch in 'ab\Ncd':
...     print ch
...
a
b
\
N
c
d

The code never replace \ followed by N.

How about call replace multiple times?

for old, new in map_dict.iteritems():
    line = line.replace(old, new)

answered Jun 25 '14 at 15:30

falsetru

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Thank you. But the problem is that the program can't do other replacing jobs like '[':'(' /N alone doesn't seem to be the source of the problem. – user3123767 Jun 25 '14 at 15:40
@user3123767, Did you try the way I suggested? (with `print`) – falsetru Jun 25 '14 at 15:48
@user3123767, You should put `print` statement after the `for` loop. – falsetru Jun 25 '14 at 16:00
It says unexpected indent. So I changed indentation. Then it says unindent doesn't match any outer indentation level. – user3123767 Jun 25 '14 at 16:03
Thank you. I marked your answer. By the way why didn't the first code in my question work? – user3123767 Jun 25 '14 at 16:11
@user3123767, You should dedent the `print` statement. BTW `print` statement with trailing `,` print additional space. – falsetru Jun 25 '14 at 16:19

Python code for replacing texts not working

1 Answers1