How to turn on "-Wall"?

[capn-freako]

How do I enable warrnings? I would like to achieve the equivalent of "-Wall".

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[ghost]

IHaskell does support -Wall through its :set command. The only issue is that it leads to extra warnings being displayed, which come from the operations that are internal to IHaskell.

For example:

$ jupyter console --kernel haskell         
Jupyter Console 4.0.2

[ZMQTerminalIPythonApp] Loading IPython extension: storemagic

In [1]: :set -Wall

<interactive>:1:5: Warning: This binding for ‘it’ shadows the existing binding defined at <interactive>:1:1

<interactive>:1:5: Warning: Defined but not used: ‘pipe_var_77748799787913499675’

<interactive>:1:5: Warning: This binding for ‘it_var_77748799787913499675’ shadows the existing binding defined at <interactive>:1:5

<interactive>:1:5: Warning: This binding for ‘it’ shadows the existing binding defined at <interactive>:1:1

In [2]: map (+1) [1..5]

<interactive>:1:5: Warning: This binding for ‘it’ shadows the existing binding defined at <interactive>:1:1

<interactive>:1:5: Warning: Defined but not used: ‘pipe_var_22949703872331401261’

<interactive>:1:1: Warning:
    Defaulting the following constraint(s) to type ‘Integer’
      (Enum b0) arising from a use of ‘it’ at <interactive>:1:1-15
      (Num b0) arising from a use of ‘it’ at <interactive>:1:1-15
      (Show b0) arising from a use of ‘print’ at <interactive>:1:1-15
    In the first argument of ‘print’, namely ‘it’
    In a stmt of an interactive GHCi command: print it

<interactive>:1:5: Warning: This binding for ‘it_var_22949703872331401261’ shadows the existing binding defined at <interactive>:1:5

<interactive>:1:5: Warning: This binding for ‘it’ shadows the existing binding defined at <interactive>:1:1

<interactive>:1:5: Warning: This binding for ‘it’ shadows the existing binding defined at <interactive>:1:1

<interactive>:1:5: Warning: Defined but not used: ‘pipe_var_70387233140126141060’

<interactive>:1:5: Warning: This binding for ‘it_var_70387233140126141060’ shadows the existing binding defined at <interactive>:1:5

<interactive>:1:5: Warning: This binding for ‘it’ shadows the existing binding defined at <interactive>:1:1
[2,3,4,5,6]

[ghost]

@capn-freako To see why warnings don't show in the notebook, take a look at #612.

[gibiansky]

In addition to that issue, it seems like we should disable warnings before the IHaskell internal code, and then re-enable warnings afterwards (if they were enabled at all). We'll need to figure out how to do that...

[Eoksni]

I think the vast majority (if not all) of the warnings caused by ihaskell internals are -Wname-shadowing. At least I've only seen those (but I'm using ihaskell for a very little time, so I might be wrong).

But if we could enable all the warnings except -Wname-shadowing and display those warnings in the notebook instead of the console, that already would be super useful and I think it is much easier to implement than disabling/enabling warning for ihaskell internals.

I'd be willing to make a PR if somebody could point me at the file where to start looking from.

[vaibhavsagar]

This might be a good place to start: Evaluate.hs