[Haskell-beginners] How to understand the type "ShowS"?

[Shrivats]

What does `show "asdf"` give you in ghci? What Lyndon showed you was that
this function is equivalent to `shows x s = show x ++ s`.

Have fun,

Shrivats
On Sep 24, 2013 5:09 PM, "yi lu" <zhiwudazhanjiangshi at gmail.com> wrote:

>
> On Tue, Sep 24, 2013 at 6:54 PM, Lyndon Maydwell <maydwell at gmail.com>wrote:
>
>> Looks like it's a convenience for building up a compositions of "Show"s.
>>
>> ShowS is indeed a synonym for a function. The type of shows alone isn't
>> enough to figure out how it behaves exactly, but testing it out in GHCi is
>> telling:
>>
>>
>> > [Prelude] λ :i ShowS
>> > type ShowS = String -> String -- Defined in `GHC.Show'
>> > [Prelude] λ :i shows
>> > shows :: Show a => a -> ShowS -- Defined in `GHC.Show'
>> > [Prelude] λ shows "asdf" "qwer"
>> > "\"asdf\"qwer"
>>
>> I don't know the meaning of this result.
>
>
>
>>
>> On Tue, Sep 24, 2013 at 8:15 PM, yi lu <zhiwudazhanjiangshi at gmail.com>wrote:
>>
>>> Prelude> :i ShowS
>>> type ShowS = String -> String     -- Defined in `GHC.Show'
>>>
>>> It is a type of a function? I cannot understand this type, and don't
>>> know how to create functions of this type.
>>>
>>> And this function "shows"
>>>
>>> Prelude> :i shows
>>> shows :: Show a => a -> ShowS     -- Defined in `GHC.Show'
>>>
>>> I don't know how this function works.
>>>
>>> Yi
>>>
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