That's a very hard question. I found http://groups.google.com/group/sage-devel/browse_thread/thread/7499c3e834bd675b/5b2f8d39f4137684?lnk=gst&q=_unsafe_mutate+power+series#5b2f8d39f4137684 for more background.
Cheers, Michael Am 02.08.2010 um 11:08 schrieb Sebastian Pancratz: > On 2 Aug, 09:57, Michael Brickenstein <brickenst...@mfo.de> wrote: >> I just tried it and the standard library functions also use that >> "optimization". >> >> In [1]: from copy import copy >> >> In [2]: l="slkl" >> >> In [3]: copy(l) is l >> Out[3]: True >> >> Cheers, >> Michael > > Perhaps my knowledge of Python isn't strong enough, but I guess > strings actually *are* immutable, as opposed to the way that > polynomials in Sage are only kind of immutable. This makes it > perfectly alright to have "copy" return the object itself. However, > if you are a user of Sage wanting to use the "_unsafe_mutate" option, > I think you really want copy to give you an independent "copy", don't > you? > > Kind regards, > Sebastian > > -- > To post to this group, send an email to sage-devel@googlegroups.com > To unsubscribe from this group, send an email to > sage-devel+unsubscr...@googlegroups.com > For more options, visit this group at > http://groups.google.com/group/sage-devel > URL: http://www.sagemath.org ------------------------------------------- Michael Brickenstein Mathematisches Forschungsinstitut Oberwolfach gGmbH Schwarzwaldstr. 9 - 11 77709 Oberwolfach Tel.: 07834/979-31 Fax: 07834/979-38 -- To post to this group, send an email to sage-devel@googlegroups.com To unsubscribe from this group, send an email to sage-devel+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org
