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</o:shapelayout></xml><![endif]--></head><body lang=FR-CA link=blue vlink=purple><div class=WordSection1><div><div><div><p class=MsoNormal style='margin-left:35.4pt'><span lang=EN-CA>On Mon, Mar 28, 2016 at 8:54 AM, Émanuel Barry <</span><a href="mailto:vgr255@live.ca" target="_blank"><span lang=EN-CA>vgr255@live.ca</span></a><span lang=EN-CA>> wrote:<o:p></o:p></span></p><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0cm 0cm 0cm 6.0pt;margin-left:4.8pt;margin-right:0cm'><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:35.4pt'><span lang=EN-CA style='font-size:11.0pt;font-family:Consolas;color:#1F497D'>I wonder how reasonable it would be to add a new keyword to open that would .close() the file object upon a single write/read. Consider:</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:35.4pt'><span lang=EN-CA style='font-size:11.0pt;font-family:Consolas;color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:35.4pt'><span lang=EN-CA style='font-size:11.0pt;font-family:Consolas;color:#1F497D'>data = open("foo.txt", "r", close_after_use=True).read()</span><o:p></o:p></p></div></div></blockquote><div><p class=MsoNormal style='margin-left:35.4pt'><o:p> </o:p></p></div><div><p class=MsoNormal style='margin-left:35.4pt'>it makes it a tiny bit shorter than using "with", but doesn't solve Nick's mental model issue -- the user still needs to be thinking about the fact that they are creating a file object and that it needs to be closed when you are done with it.<o:p></o:p></p></div><div><p class=MsoNormal style='margin-left:35.4pt'><o:p> </o:p></p></div><div><p class=MsoNormal style='margin-left:35.4pt'>and I"m not sure how you would define "use" -- any i.o. opeartion? i.e.:<o:p></o:p></p></div><div><p class=MsoNormal style='margin-left:35.4pt'><o:p> </o:p></p></div><p class=MsoNormal style='margin-left:35.4pt'><span style='font-family:"Courier New"'>infile = open("foo.txt", "r", close_after_use=True)<br>first_line = infile.readline()</span><o:p></o:p></p></div><div><p class=MsoNormal style='margin-left:35.4pt'><o:p> </o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:0cm;margin-right:0cm;margin-bottom:12.0pt;margin-left:35.4pt'><span style='font-family:"Courier New"'>now what is the state of infile? a closed file object?</span><o:p></o:p></p></div><div><p class=MsoNormal><span lang=EN-CA style='color:#1F497D'>Sure. The keyword really could benefit from a better name, but it might solve some part of the issue. It doesn’t solve the mental model issue though, but to be fair, </span><span lang=EN-CA style='font-family:Consolas;color:#1F497D'>open()</span><span lang=EN-CA style='color:#1F497D'> should always be wrapped in a context manager (IMO, anyway).<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-CA style='color:#1F497D'>-Emanuel<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-size:11.0pt;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal style='margin-left:35.4pt'><span lang=EN-CA>exactly why context managers were introduced:<o:p></o:p></span></p></div></div><div><p class=MsoNormal style='margin-left:35.4pt'><span lang=EN-CA style='font-family:"Courier New"'><o:p> </o:p></span></p></div><p class=MsoNormal style='margin-left:35.4pt'><span lang=EN-CA style='font-family:"Courier New"'>w</span><span style='font-family:"Courier New"'>ith open("foo.txt", "r", close_after_use=True) as infile:<br> first_line = infile.readline()<br><br>something_else...</span><o:p></o:p></p><div><p class=MsoNormal style='margin-left:35.4pt'><o:p> </o:p></p></div><div><p class=MsoNormal style='margin-left:35.4pt'>now it's pretty clear that <span style='font-family:"Courier New"'>infile</span> is no longer a useful object.<o:p></o:p></p></div><div><p class=MsoNormal style='margin-left:35.4pt'><o:p> </o:p></p></div><div><p class=MsoNormal style='margin-left:35.4pt'>-CHB<o:p></o:p></p></div><div><div><p class=MsoNormal><o:p> </o:p></p></div></div></div></div></body></html>