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From: "Prasad, Ramit" <ramit.prasad@jpmorgan.com>
To: Andriy Kornatskyy <andriy.kornatskyy@live.com>, "python-list@python.org" <python-list@python.org>
Subject: RE: duck typing assert
Thread-Topic: duck typing assert
Thread-Index: AQHNvglkFIDQFeTGJkmEObVb7xMqfpfhAxoAgABXsICAAEZZAIAAIu8A
Date: Fri, 9 Nov 2012 17:37:29 +0000
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Andriy Kornatskyy wrote:=0D=0A> =0D=0A> Thank you for all comments=2E=0D=0A=
> =0D=0A> > It=A0makes very good sense to say:=0D=0A> >=0D=0A> > duckmatch(=
IFoo)=2Ecompare(Foo)=0D=0A> =0D=0A> Since we do duck match of IFoo=2E=2E=2E=
 but there is no `duck match`, there is `duck test`=2E=A0I believe instead =
of=0D=0A> `compare` is more readable with `equals`=2E Than it is more from=
=A0mathematics - precise answer=2E=2E=2E=A0that you can not=0D=0A> guarante=
e at all in dynamic programming language=2E So it false to use such wording=
 to reflect this check=2E We can=0D=0A> only make an assumption that one lo=
oks like the other (similar)=2E=2E=2E with some limitation of cause=2E=2E=
=2E=0D=0A> understanding what is `duck test`=2E=0D=0A> =0D=0A> http://en=2E=
wikipedia=2Eorg/wiki/Duck_test=0D=0A> =0D=0A> The intent is to make such la=
nguage `construct` so it reads as English sentence that make sense, and not=
=0D=0A> mandatory `pythonic` way (readability counts, java smokes aside)=2E=
=0D=0A> =0D=0A> is_similar(Foo)=2Eto(IFoo) # <=3D but we lost `duck test` s=
ense here?=0D=0A> =0D=0A> Words `looks` and `like` are coming from duck tes=
t and point also direction:=0D=0A> =0D=0A> # 1=0D=0A> looks(Foo)=2Elike(IFo=
o, notice=3D['__len__'], ignore_funcs=3D['foo'], ignore_argspec['bar'])=0D=
=0A> =0D=0A> English sentence equivalent: if functions in Foo looks like on=
e in IFoo than, probably, IFoo can be replaced=0D=0A> with Foo; notice to c=
heck __len__, it is safe to ignore function `foo` and arguments passed to `=
bar`=2E=0D=0A> =0D=0A> # 2=0D=0A> looks(Foo, notice=3D['__len__'], ignore_f=
uncs=3D['foo'], ignore_argspec['bar'])=2Elike(IFoo)=0D=0A> =0D=0A> English =
sentence equivalent:=A0while looking at Foo notice to check `__len__`, it i=
s safe to ignore function `foo`=0D=0A> and=A0arguments passed to `bar`, tha=
n probably it like IFoo=2E=0D=0A=0D=0AWhat about?=0D=0A=0D=0Aduck(Foo)=2Eeq=
uivalent_to(IFoo, <kwargs>) =0D=0Aduck(Foo)=2Ematches(IFoo, <kwargs>)=0D=0A=
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