| module Query = [%graphql | |
| {| | |
| query { | |
| someFieldWithInterfaceType { | |
| id | |
| ...on ImplA { | |
| a_only | |
| } | |
| ...on ImplB { | |
| b_only |
| (* SIMPLE FUNCTIONS OVER INTEGERS *) | |
| let multiple_of n d = | |
| n mod d = 0;; | |
| let integer_square_root n = | |
| int_of_float (sqrt (float n));; | |
| (* PRIME NUMBERS *) | |
| let rec gcd n m = | |
| match (n, m) with |
| module type Set = sig | |
| type 'a t | |
| val empty : 'a t | |
| val isEmpty : 'a t -> bool | |
| end | |
| module ListSet : Set = struct | |
| type 'a t = 'a list | |
| let empty = [] | |
| let isEmpty l = l == [] |
Hi folks, I just wanna share my story on my first day trying Cabal/Stack.
So I was learning Haskell for half a semester but only live within ghci and runhaskell. But today I was thinking of playing with /write-you-a-haskell/chapter4/untyped so I pulled it down.
I was first trying to follow the README.md which asked me to do cabal run. It failed and gave me errors on the ambiguous usage of <>, I realized cabal is using my global GHC version and it might be some breaking changes there. (since it's Haskell)
I heard stack can solve this problem by having multiple GHC so I changed to looking into that. So I run stack build, see the new GHC being downloaded, but failed. The resolver of the project is 7.8.4 and the problem is ar permission errors on OS X 10.11 El Capitan with GHC 7.8.4 . I tried several workarounds posted in the issue page but none of them works.
Aft
| {-# LANGUAGE | |
| GADTs, | |
| ExistentialQuantification | |
| #-} | |
| import Control.Monad | |
| import Data.IORef | |
| import Data.Sequence | |
| import Data.Foldable |
| import 'package:flutter/material.dart'; | |
| /// A TextField that maintain selection state like React Native | |
| class TextInput extends StatefulWidget { | |
| TextInput({@required this.decoration, @required this.text, @required this.onChanged}); | |
| final String text; | |
| final InputDecoration decoration; | |
| final Function onChanged; |
A Pen by Anonasaurus Rex on CodePen.
| // 试了两种方式模拟： | |
| class Super { | |
| constructor() { | |
| this.x = "super" | |
| } | |
| }; | |
| // 这样的话也是 own property | |
| new Super().hasOwnProperty('x') // true |
| /** | |
| class Super { | |
| x = "super" | |
| } | |
| */ | |
| class Super { | |
| constructor() { |