[Python-checkins] cpython (3.3): #13510: clarify that f.readlines() is note necessary to iterate over a file.

[ezio.melotti]

http://hg.python.org/cpython/rev/1e8be05a4039
changeset:   83395:1e8be05a4039
branch:      3.3
parent:      83393:ad481c95a1d4
user:        Ezio Melotti <ezio.melotti at gmail.com>
date:        Mon Apr 15 19:08:31 2013 +0300
summary:
  #13510: clarify that f.readlines() is note necessary to iterate over a file.  Patch by Dan Riti.

files:
  Doc/library/io.rst           |   3 +++
  Doc/tutorial/inputoutput.rst |  19 ++++---------------
  Misc/ACKS                    |   1 +
  3 files changed, 8 insertions(+), 15 deletions(-)


diff --git a/Doc/library/io.rst b/Doc/library/io.rst
--- a/Doc/library/io.rst
+++ b/Doc/library/io.rst
@@ -298,6 +298,9 @@
       to control the number of lines read: no more lines will be read if the
       total size (in bytes/characters) of all lines so far exceeds *hint*.
 
+      Note that it's already possible to iterate on file objects using ``for
+      line in file: ...`` without calling ``file.readlines()``.
+
    .. method:: seek(offset, whence=SEEK_SET)
 
       Change the stream position to the given byte *offset*.  *offset* is
diff --git a/Doc/tutorial/inputoutput.rst b/Doc/tutorial/inputoutput.rst
--- a/Doc/tutorial/inputoutput.rst
+++ b/Doc/tutorial/inputoutput.rst
@@ -300,18 +300,8 @@
    >>> f.readline()
    ''
 
-``f.readlines()`` returns a list containing all the lines of data in the file.
-If given an optional parameter *sizehint*, it reads that many bytes from the
-file and enough more to complete a line, and returns the lines from that.  This
-is often used to allow efficient reading of a large file by lines, but without
-having to load the entire file in memory.  Only complete lines will be returned.
-::
-
-   >>> f.readlines()
-   ['This is the first line of the file.\n', 'Second line of the file\n']
-
-An alternative approach to reading lines is to loop over the file object. This is
-memory efficient, fast, and leads to simpler code::
+For reading lines from a file, you can loop over the file object. This is memory
+efficient, fast, and leads to simple code::
 
    >>> for line in f:
    ...     print(line, end='')
@@ -319,9 +309,8 @@
    This is the first line of the file.
    Second line of the file
 
-The alternative approach is simpler but does not provide as fine-grained
-control.  Since the two approaches manage line buffering differently, they
-should not be mixed.
+If you want to read all the lines of a file in a list you can also use
+``list(f)`` or ``f.readlines()``.
 
 ``f.write(string)`` writes the contents of *string* to the file, returning
 the number of characters written. ::
diff --git a/Misc/ACKS b/Misc/ACKS
--- a/Misc/ACKS
+++ b/Misc/ACKS
@@ -1003,6 +1003,7 @@
 Jean-Claude Rimbault
 Vlad Riscutia
 Wes Rishel
+Dan Riti
 Juan M. Bello Rivas
 Davide Rizzo
 Anthony Roach

-- 
Repository URL: http://hg.python.org/cpython