[Tutor] Unnecessary comprehension warning

[boB Stepp]

On Sat, Jun 6, 2020 at 9:29 PM DL Neil via Tutor <tutor at python.org> wrote:
>
> On 7/06/20 2:19 PM, boB Stepp wrote:
> > Continuing "Exercise 3.12: Using your library module" in "3.4 Modules" at
> > https://dabeaz-course.github.io/practical-python/Notes/03_Program_organization/04_Modules.html.
> >
> >
> > I rewrote another function in report.py, read_prices(), to make use of the
> > parse_csv() function in the fileparse module.  The rewritten function is:
> >
> > def read_prices(filename: str) -> Dict[str, float]:
> >      """Read a file of stock prices and load them into a dictionary."""
> >      prices = fileparse.parse_csv(filename, types=[str, float],
> > has_headers=False)
> >      stock_prices = {stock_name: stock_price for stock_name, stock_price
> > in prices}
> >      return stock_prices
> >
> > pylint complains with:
> >
> > report.py|25 col 1 warning| unnecessary-comprehension: Unnecessary use
> > of a comprehension
> >
> > The dictionary comprehension I'm now using replaces a lengthier for loop
> > with indexing instead of nice names.  Am I truly doing things in a bad
> > Python style as the linter is complaining?  Should I be doing this
> > differently?
>
>
> The name "prices" is defined and then used, but enjoys no further reference.
>
> What happens (from PyLint's PoV) if you make the two lines into one?
> (overly-complicated and ugly though it would be)

Strangely, it makes no difference, same warning.



-- 
boB