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Date: Tue, 4 Dec 2012 17:17:56 -0800 (PST)
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Subject: Re: Good use for itertools.dropwhile and itertools.takewhile
From: Nick Mellor <thebalancepro@gmail.com>
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Xref: csiph.com comp.lang.python:34267

Hi Terry,

For my money, and especially in your versions, despite several expert solut=
ions using other features, itertools has it. It seems to me to need less nu=
tting out than the other approaches. It's short, robust, has a minimum of s=
ymbols, uses simple expressions and is not overly clever. If we could just =
get used to using takewhile.

takewhile mines for gold at the start of a sequence, dropwhile drops the dr=
oss at the start of a sequence.

Thanks all for your interest and your help,

Best,

Nick

Terry's implementations:

> from itertools import takewhile
>=20
> def allcaps(word): return word =3D=3D word.upper()
>=20
>=20
>=20
> def split_product_itertools(s):
>=20
>      product =3D ' '.join(takewhile(allcaps, s.split()))
>=20
>      return product, s[len(product)+1:]
>=20
>=20
>=20
> print(split_product_itertools("CAPSICUM RED fresh from QLD"))
>=20
>  >>>
>=20
> ('CAPSICUM RED', 'fresh from QLD')
>=20
>=20
>=20
> [if there could be surplus whitespace], the same idea applies to the spli=
t list.
>=20
>=20
>=20
> def split_product_itertools(s):
>=20
>      words =3D s.split()
>=20
>      product =3D list(takewhile(allcaps, words))
>=20
>      return ' '.join(product), ' '.join(words[len(product):])
>=20