Hi,

Part of what you would like is already there. If you run ghci with -Wall, you will get warnings about defaulting polymorphic expressions.

```

Prelude> 1

<interactive>:2:1: Warning:

Defaulting the following constraint(s) to type ‘Integer’

(Num a0) arising from a use of ‘it’ at <interactive>:2:1

(Show a0) arising from a use of ‘print’ at <interactive>:2:1

In the first argument of ‘print’, namely ‘it’

In a stmt of an interactive GHCi command: print it

Prelude>

```

--trevor

On Thu, Apr 28, 2016 at 8:05 AM Johannes Waldmann <johannes.waldmann@htwk-leipzig.de> wrote:

Hi,

> If you ask GHCi to *evaluate* a polymorphic expression, then it will ...

Sure, I understand the motivation for defaulting,
and I am not suggesting to change anything there.

What I am saying is that I see no way to have ghci show
* the defaulted type,
* or the even the fact that defaulting did happen.

- J.

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