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Re: How can I remove the first line of a multi-line string? (SOLVED)

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In article <mailman.500.1378139057.19984.python-list@python.org>,
 Anthony Papillion <papillion@gmail.com> wrote:

> On 09/02/2013 11:12 AM, Chris “Kwpolska” Warrick wrote:
> > On Mon, Sep 2, 2013 at 6:06 PM, Anthony Papillion <papillion@gmail.com> 
> > wrote:
> >> Hello Everyone,
> >>
> >> I have a multi-line string and I need to remove the very first line from
> >> it. How can I do that? I looked at StringIO but I can't seem to figure
> >> out how to properly use it to remove the first line. Basically, I want
> >> to toss the first line but keep everything else.  Can anyone put me on
> >> the right path? I know it is probably easy but I'm still learning Python
> >> and don't have all the string functions down yet.
> >>
> >> Thanks,
> >> Anthony
> >> --
> >> http://mail.python.org/mailman/listinfo/python-list
> > 
> > Use split() and join() methods of strings, along with slicing.  Like this:
> > 
> >     fullstring = """foo
> >     bar
> >     baz"""
> > 
> >     sansfirstline = '\n'.join(fullstring.split('\n')[1:])
> > 
> > The last line does this:
> > 1. fullstring.split('\n') turns it into a list of ['foo', 'bar', 'baz']
> > 2. the [1:] slice removes the first element, making it ['bar', 'baz']
> > 3. Finally, '\n'.join() turns the list into a string separated by
> > newlines ("""bar
> > baz""")
> 
> This, of course, worked like a charm. I really need to study the string
> methods. In the work I'm doing they are going to come in very handy.
> Thank you, Chris!

Let me toss out a couple of other possibilities.  Not necessarily 
better, but if you're learning about strings, you might as well learn 
some other ways to do it:


s = """foo                                                                                          
     
bar                                                                                            
     
baz"""

print "using index..."
i = s.index('\n')
print s[i+1:]

print "using regex..."
import re
print re.sub(r'^[^\n]*\n', '', s)


I'll admit, the split/slice/join solution is probably the easiest to 
implement (and to understand when you're reading the code).  But, it 
copies all the data twice; once when split() runs, and again when join() 
runs.  Both the index and regex solutions should only do a single copy.  
For huge strings, this might matter.  For a three-liner as in your 
example, it doesn't make any difference.

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Re: How can I remove the first line of a multi-line string? (SOLVED) Anthony Papillion <papillion@gmail.com> - 2013-09-02 11:24 -0500
  Re: How can I remove the first line of a multi-line string? (SOLVED) Roy Smith <roy@panix.com> - 2013-09-02 13:07 -0400
    Re: How can I remove the first line of a multi-line string? (SOLVED) Fábio Santos <fabiosantosart@gmail.com> - 2013-09-11 13:08 +0100
      Re: How can I remove the first line of a multi-line string? (SOLVED) Roy Smith <roy@panix.com> - 2013-09-11 09:03 -0400
    Re: How can I remove the first line of a multi-line string? (SOLVED) Terry Reedy <tjreedy@udel.edu> - 2013-09-11 08:42 -0400

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