IxJS not compatible with typescript 2.7

[patsissons]

IxJS version:
2.3.4

Code to reproduce:
this is a type declaration error, so any usage of tsc with the current version of ix will fail.

Expected behavior:
no compilation errors

Actual behavior:
example output (using the webpack at-loader)

ERROR in [at-loader] ./node_modules/ix/add/asynciterable-operators/concat.ts:63:10
    TS2556: Expected 1-6 arguments, but got 1 or more.

ERROR in [at-loader] ./node_modules/ix/add/asynciterable-operators/merge.ts:63:10
    TS2556: Expected 1-6 arguments, but got 1 or more.

ERROR in [at-loader] ./node_modules/ix/add/iterable-operators/concat.ts:54:10
    TS2556: Expected 1-6 arguments, but got 1 or more.

Additional information:
There are some missing exports on the above 3 mentioned files that declare the catch all function signatures (exports without implementation). I'm not completely certain what changed from 2.6.x to 2.7.x, but there was some change that now requires these additional exports when overloading a function signature. I will be publishing a PR for this fix shortly.

[patsissons]

Until #215 is merged, there is a work around by performing some unconventional augmentations.

import { IterableX } from 'ix/iterable/iterablex';
import { AsyncIterableX } from 'ix/asynciterable/asynciterablex';

declare module 'ix/iterable/concat' {
  // @ts-ignore: static function overload augmentation
  function concat<T>(source: IterableX<T>, ...args: Iterable<T>[]): IterableX<T>;
}

declare module 'ix/asynciterable/concat' {
  // @ts-ignore: static function overload augmentation
  function concat<T>(source: AsyncIterableX<T>, ...args: AsyncIterable<T>[]): AsyncIterableX<T>;
}

declare module 'ix/asynciterable/merge' {
  // @ts-ignore: static function overload augmentation
  function merge<T>(source: AsyncIterableX<T>, ...args: AsyncIterable<T>[]): AsyncIterableX<T>;
}

[trxcllnt]

thanks @patsissons, I was worried we might see some issues with 2.7. Will validate the fix (and maybe fix CI) later tonight.