This is pretty easy to write without any syntax changes, just using a
higher-order function `compose()` (possible implementation at foot).
Again, I'll assume auto-currying like the map/filter versions of those
functions in toolz, as Steven does:
> result = (myfile.readlines()
> -> map(str.strip)
> -> filter( lambda s: not s.startwith('#') )
> -> sorted
> -> collapse # collapse runs of identical lines
> -> extract_dates
> -> map(date_to_seconds)
> -> min
> )
>
result = compose(map(str.strip),
filter(lambda s: not startswith('#'),
sorted,
collapse,
extract_dates,
map(date_to_seconds),
min
)(myfile.readlines())
Pretty much exactly the same thing with just a utility HOF. There's one
that behaves right in `toolz`/`cytoolz`, or I've used this one in some
publications and teaching material:
def compose(*funcs):
"""Return a new function s.t.
compose(f,g,...)(x) == f(g(...(x)))
"""
def inner(data, funcs=funcs):
result = data
for f in reversed(funcs):
result = f(result)
return result
return inner
--
Keeping medicines from the bloodstreams of the sick; food
from the bellies of the hungry; books from the hands of the
uneducated; technology from the underdeveloped; and putting
advocates of freedom in prisons. Intellectual property is
to the 21st century what the slave trade was to the 16th.
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