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standard function to zip a list with sequential numbers

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  standard function to zip a list with sequential numbers Pavel <pauldontspamtolk@removeyourself.dontspam.yahoo> - 2018-10-14 19:32 -0400
    Re: standard function to zip a list with sequential numbers Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-10-15 02:55 +0100
      Re: standard function to zip a list with sequential numbers Pavel <pauldontspamtolk@removeyourself.dontspam.yahoo> - 2018-10-14 22:47 -0400
        Re: standard function to zip a list with sequential numbers Paul Rubin <no.email@nospam.invalid> - 2018-10-14 20:02 -0700
        Re: standard function to zip a list with sequential numbers Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-10-15 16:43 +0100
        Re: standard function to zip a list with sequential numbers Patrick Roemer <sangamon@netcologne.de> - 2018-10-16 17:41 +0200
          Re: standard function to zip a list with sequential numbers Paul Rubin <no.email@nospam.invalid> - 2018-10-16 10:56 -0700
            Re: standard function to zip a list with sequential numbers Pavel <pauldontspamtolk@removeyourself.dontspam.yahoo> - 2018-10-17 01:43 -0400

#494 — standard function to zip a list with sequential numbers

Is there a standard Haskell function to the effect of

zip [0..]
or
zip [1..]
?

Thank you,
-Pavel

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#495

Pavel <pauldontspamtolk@removeyourself.dontspam.yahoo> writes:

> Is there a standard Haskell function to the effect of
>
> zip [0..]
> or
> zip [1..]
> ?

I don't know what either that short-hand, nor the wording used in the
subject ("zip a list with sequential numbers") is supposed to mean.

If you are fining it hard to specify what you mean, either explain it by
using some other programming language, or at least give a few examples
of what you want.  If zip [0..] should work, what do you want zip [0..]
to be?

-- 
Ben.

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#496

Ben Bacarisse wrote:
> Pavel <pauldontspamtolk@removeyourself.dontspam.yahoo> writes:
> 
>> Is there a standard Haskell function to the effect of
>>
>> zip [0..]
>> or
>> zip [1..]
>> ?
> 
> I don't know what either that short-hand, nor the wording used in the
> subject ("zip a list with sequential numbers") is supposed to mean.
To rephrase the question, is there a standard name for a function like
"nmb" below:

nmb :: [a] -> [(Int, a)]
nmb = zip [1..]

and/or like "nmb0" below:

nmb0 :: [a] -> [(Int, a)]
nmb0 = zip [0..]

> 
> If you are fining it hard to specify what you mean, either explain it by
> using some other programming language, or at least give a few examples
> of what you want.  If zip [0..] should work, what do you want zip [0..]
> to be?
[a] -> [(Int, a)]

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#497

Pavel <pauldontspamtolk@removeyourself.dontspam.yahoo> writes:
> [a] -> [(Int, a)]

Integral n => [a] -> [(n, a)]

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#498

Pavel <pauldontspamtolk@removeyourself.dontspam.yahoo> writes:
<snip>
> To rephrase the question, is there a standard name for a function like
> "nmb" below:
>
> nmb :: [a] -> [(Int, a)]
> nmb = zip [1..]

Oh I see -- and now your earlier description makes sense!  But no there
isn't a standard name for zip [1..].

-- 
Ben.

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#501

Responding to Pavel:
> To rephrase the question, is there a standard name for a function like
> "nmb" below:
> 
> nmb :: [a] -> [(Int, a)]
> nmb = zip [1..]
> 
> and/or like "nmb0" below:
> 
> nmb0 :: [a] -> [(Int, a)]
> nmb0 = zip [0..]

What should it be named? In Scala, nmb0 is zipWithIndex - but that's
already longer than the Haskell implementation...

Best regards,
Patrick

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#503

Patrick Roemer <sangamon@netcologne.de> writes:
> What should it be named? In Scala, nmb0 is zipWithIndex - but that's
> already longer than the Haskell implementation...

In Python it's "enumerate", but in Haskell I don't think a special
purpose function is needed.  "zip [0..]" works perfectly well.

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#504

Paul Rubin wrote:
> Patrick Roemer <sangamon@netcologne.de> writes:
>> What should it be named? In Scala, nmb0 is zipWithIndex - but that's
>> already longer than the Haskell implementation...
> 
> In Python it's "enumerate", but in Haskell I don't think a special
> purpose function is needed.  "zip [0..]" works perfectly well.
Thanks!

I don't like how it pollutes the code when I need to use it many times in one
function; also composition with other functions is even cleaner if it's one
word, even if it's long (for readability, 1 token vs 5 means makes lots of
difference).

But it's ok -- just did not want to pollute peoples' brains with a new name for
a thing that might have already had a name. I thought of enum[erate] but it
seems to be used for different things in Haskell. Somehow never thought of
borrowing from Scala -- thanks Patrick for the idea. zipWith0BasedIndex,
zipWith1BasedIndex it is now -- haters are welcomed (just kidding).

-Pavel

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