[Haskell-beginners] import question

[Galaxy Being]

As I've said, working at the ghci REPL,

import Data.Decimal
dList :: [Decimal]
dList = [1.00,1.01..2.00]
main = print dList

errors out

: <interactive>:76:11-17: error:
:     Not in scope: type constructor or class `Decimal'



On Wed, Feb 17, 2021 at 8:37 PM Bob Ippolito <bob at redivi.com> wrote:

> You don't need to do any rounding if the list is already Decimal.
>
> If you wanted to format a Double with some specific decimal representation
> you could look at Numeric.showFFloatAlt or similar.
>
> import Data.Decimal
>
> dList :: [Decimal]
> dList = [1.00,1.01..2.00]
>
> main = print dList
>
>
>
> On Wed, Feb 17, 2021 at 5:27 PM Galaxy Being <borgauf at gmail.com> wrote:
>
>> I'm trying to create a list of real numbers with a two-decimal interval,
>> a la
>>
>> > [1.0,1.01,1.02,...1.99,2.00]
>>
>> however, I get the float approximation problem
>>
>>
>> [1.0,1.01,1.02,1.03,1.04,1.05,1.06,1.07,1.08,1.09,1.1,1.11,1.12,1.1300000000000001,1.1400000000000001,...
>>
>> So I attempted to compensate with
>>
>> import Data.Decimal
>> map (roundTo 2) [1.00,1.01..2.0]
>>
>> I don't have to do it this way if there is another rounding function to
>> correct the float overrun issue.
>>
>>
>>
>> On Wed, Feb 17, 2021 at 2:43 PM Francesco Ariis <fa-ml at ariis.it> wrote:
>>
>>> Il 17 febbraio 2021 alle 14:17 Galaxy Being ha scritto:
>>> > How would I install it globally? I'm not using projects, I'm just at
>>> the
>>> > ghci REPL.
>>>
>>> Most likely
>>>
>>>     cabal install --lib Decimal
>>>
>>> Check what Tom has said too —F
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