Python readline() from a string?

Question

In python, is there a built-in way to do a readline() on string? I have a large chunk of data and want to strip off just the first couple lines w/o doing split() on the whole string.

Hypothetical example:

def handleMessage(msg):    headerTo  = msg.readline()    headerFrom= msg.readline()    sendMessage(headerTo,headerFrom,msg)  msg = "Bob Smith\nJane Doe\nJane,\nPlease order more widgets\nThanks,\nBob\n" handleMessage(msg) 

I want this to result in: sendMessage("Bob Smith", "Jane Doe", "Jane,\nPlease order...")

I know it would be fairly easy to write a class that does this, but I'm looking for something built-in if possible.

EDIT: Python v2.7

Answer 1

In Python 3, you can use io.StringIO:

>>> msg = "Bob Smith\nJane Doe\nJane,\nPlease order more widgets\nThanks,\nBob\n" >>> msg 'Bob Smith\nJane Doe\nJane,\nPlease order more widgets\nThanks,\nBob\n' >>> >>> import io >>> buf = io.StringIO(msg) >>> buf.readline() 'Bob Smith\n' >>> buf.readline() 'Jane Doe\n' >>> len(buf.read()) 44 

---

In Python 2, you can use StringIO (or cStringIO if performance is important):

>>> import StringIO >>> buf = StringIO.StringIO(msg) >>> buf.readline() 'Bob Smith\n' >>> buf.readline() 'Jane Doe\n' 

Answer 2

The easiest way for both python 2 and 3 is using string's method splitlines(). This returns a list of lines.

>>> "some\nmultilene\nstring\n".splitlines() 

['some', 'multilene', 'string']