removing characters from file

Question

I have a file with a bunch of events listed:

-[test123
-[test456
-[test789
test1011
test1213

I'm looking to list the items with -[, but when printing I want to remove the '-['. This is what I currently have:

f = open("file", "r").readlines()
for line in f:
    if '-[' in line:
        line.lstrip('-[')
token = line.split('_')
print token

But I'm not getting the expected result. Can anyone help with where I went wrong?

Answer 1

str.lstrip([chars])

Return a copy of the string with leading characters removed.

f = open("file", "r").readlines()
for line in f:
    if '-[' in line:
        line = line.lstrip('-[')
    print line  # modified/unmodified line without -[

You have to assign modified line to variable line

Answer 2

If you want only the lines starting with -[ :

f = open("file", "r").readlines()
for line in f:
    if '-[' in line:
        line.lstrip('-[')
        token=line.split('_')
        print token

If you want all lines but removing -[ :

f = open("file", "r").readlines()
for line in f:
    line.lstrip('-[')
    token=line.split('_')
    print token

Answer 3

lines = open("file", "r").readlines()
# to print all lines
lines = [line.lstrip('-[') for line in lines]
# to print only lines with '-['
lines = [line.lstrip('-[') for line in lines if '-[' in line]

Now you can iterate over the lines variable and perform whatever operations you want to.