Resolve cross dependency

[martinheidegger]

es5-ext is requiring a dependency on es6-iterator and es6-iterator is requiring a dependency on es5-ext. This cross dependency is not cool according to npm that dies in a Maximum call stack size exceeded message when it's trying to shrinkwrap es5-ext (and probably even other cases).

It would be awesome if es5-ext or es6-iterator could be changed to have only a one-way dependency.

[martinheidegger]

Related: https://github.com/npm/npm/issues/13730

[medikoo]

@martinheidegger it's intended and this works perfectly with normal install. It's really a bug of npm shrinkrwap, so let's solve this issue at https://github.com/npm/npm/issues/13730

[martinheidegger]

@medikoo Thank you for answering. Out of curiosity: What is the intention behind it? Even in consultation with dev-friends I couldn't make out why this would make sense. I would be very grateful for enlightenment.

[medikoo]

@martinheidegger sure:

• es5-ext is extensions for ES5, but with respect to the ES6 standard, that's e.g. the reason it provides Array.from or Array.prototype.values
• Still es5-ext doesn't provide the polyfills to new types as introduced by ES6, e.g. Set or Map, WeakMap etc.. (they're introduced with other packages). Same it doesn't provide ES6 iterator types for types that existed with ES5 e.g. Array, String, arguments (that's handled by es6-iterator package)
• Functions as Array.from or methods as Array.prototype.values consume or return ES6 iterators, that's the reasones5-ext, needs es6-iterator, and as es6-iterator uses some ES extensions from es5-ext it relies on it.