[Haskell-cafe] Change value of a variable

Keith Sheppard keithshep at gmail.com
Sun Jun 7 14:46:30 EDT 2009


I guess the short answer is that it is not possible. 'x' is immutable
and if you want a different value than 'x' that expression has to be
given a different name like:
let x=1
    y=x+2
    ...

But I'm not sure if that helps you. Haskell does things very
differently than the imperative languages and forces you to think
differently about how to solve problems. When I started learning
haskell I found that I had to think more about composing/decomposing
expressions and less about sequencing actions and side effects like
you do in most of the more popular languages (I really have come to
prefer the Haskell way). I think we may be able to give a more helpful
answer if give a more high level algorithm/use case... why do you want
to change the value of x

-Keith

On Sun, Jun 7, 2009 at 1:41 PM, ptrash<ptrash at web.de> wrote:
>
> Hi, how can I change the value of a variable.
>
> let x = 1
> x = x + 2
>
> First I set the value of x to 1. Then I want to increase it by 2. This way
> doesn't work, because I think it is a infinite expression.
>
> Is there a way to change the value?
>
>
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-- 
keithsheppard.name


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