I'm writing an application based on react-native and we know definitely we can use JavaScript codes in this project and all react projects.
But when I use below code the transpiler return Error to the simulator:
const mixer = (...arg) => arg.flat(9);
The error is: flat is not function
Why in react-native it is not define but in browser works well?
React Native uses the JavaScriptCore engine which uses the ECMA-262 spec. The spec shows clearly that .flat is not supported and it is not included in the list of transformations for babel.
Write your own or install one of the many shims available on npm.
instead of arr.flat try using this function
function flatten(arr) {
return Array.prototype.concat(...arr);
}
flatten(arr)
Is it supported on your platform? Array.prototype.flat
Link also contains implementations using reduce and concat as well as non-recursive.
const mixer = (...arg) => arg.flat(9);The error is: flat is not function
Why in
react-nativeit is not define but in browser works well?
My first guess is that the react-native transpiler is not interpreting your ...arg correctly, leading to an object that is not of Array type. You are trying to call .flat, which is a part of Array.prototype. Since arg could not be of type Array, it is unable to find .flat, thus leading to that error.
I am not certain though. Can you check the object type? You can use this code here below temporarily.
const mixer = (...arg) => { console.log(typeof arg); return []; }
What does it say? If it says Array, then you might operate on a platform that does not support that function yet. Using a polyfill can solve your problem here.
