Question

I have a file as follows:

line 1: _____
   ...
# for AAA
#export CONFIG = AAA_defconfig

# for BBB, BbB, Bbb, BBb3
#export CONFIG = BBB_defconfig

# for CCC, CcC, Ccc, Ccc1
#export CONFIG = CCC_defconfig
   ...
other lines

I want manipulate the file, so that based on the given string, I could export the right “CONFIG”, and comment the others.
e.g. if I got “CcC”, then the file would be manipulated as

line 1: _____
    ...
# for AAA
#export CONFIG = AAA_defconfig

# for BBB, BbB, Bbb, BBb3
#export CONFIG = BBB_defconfig

# for CCC, CcC, Ccc, Ccc1
export CONFIG = CCC_defconfig
    ...
other lines

what the good way to do it in python?

Thanks in advance!!

Answer 1

Then why not make it as

line = 'xxxx'
CONFIG = default_deconfig

if line == 'AAA':
    CONFIG =  AAA_defconfig
elif line == 'CCC':
    CONFIG =  CCC_defconfig
...

unless this is not a python file and you want to manipulate it. It looks like that.

In that case create a config generator which will create a config file based on the line variable.

[Edit: Based on comments]

You might have to make some adjustments but this should work.

# Simple , crude solution

f = open('file1', 'r')
manipulated_lines = []
readFirstLine = False
config = ''
configComma = ''
uncommentLine = 0
for line in f:
    tokens = line.split()

    if uncommentLine == 1:
        # this is comment line
        if tokens[0] == '#export':
            manipulated_lines.append(line[1:])
            uncommentLine = uncommentLine + 1
            continue
    elif uncommentLine > 1:
        manipulated_lines.append(line)
        continue

    if not readFirstLine: 
        config = line.rstrip('\n')
        configComma = config + ','
        readFirstLine = True

    # Process additional lines 
    manipulated_lines.append(line)

    if len(tokens) > 0 and tokens[0] == '#':
        if tokens[1] == 'for':
            if config in tokens or configComma in tokens:
                uncommentLine = uncommentLine + 1
                continue

print manipulated_lines
f.close()
fw = open('file2', 'w')
fw.writelines(manipulated_lines)
fw.close()

Input: file1

CCC
# for AAA
#export CONFIG = AAA_defconfig

# for BBB, BbB, Bbb, BBb3
#export CONFIG = BBB_defconfig

# for CCC, CcC, Ccc, Ccc1
#export CONFIG = CCC_defconfig
   ...

Output: file2

CCC
# for AAA
#export CONFIG = AAA_defconfig

# for BBB, BbB, Bbb, BBb3
#export CONFIG = BBB_defconfig

# for CCC, CcC, Ccc, Ccc1
export CONFIG = CCC_defconfig
   ...