Feature request: allow .each to accept objects

Libraries like Underscore and Lodash have implementations of each which accept both arrays and objects as parameters, calling the provided function with (value, idx) or (value, key) depending on the input type.

This could be a useful extension to bluebird, saving having to do:

something().then(_.pairs).then(([k, v] => ...)

Or the equivalent with non-es6 functions.

[NotBobTheBuilder]

Yes, you can - but also remember that this would happen part way through a Promise chain, so your suggestion would look like:

getMapFromAPI().then(object => {
   const keys = Object.keys(object);
   Promise.each(keys, (key) => {
    something( keyPair[key])
   })
})

But with my suggestion, that would be

getMapFromAPI().each((data, key) => something(data))

Which is significantly more composable.

Given that Arrays are subclasses of objects (string keys mapped to values) it makes sense IMO to “genericise” this method up to objects rather than to have to create whole new lower-level strategies for writing this type of iteration code.

[petkaantonov]

If you’re using lodash you can do

getMapFromApi().then(_).call("forEach", function() {

});

Instead of having us slowly implement every method of lodash in bluebird

^{(if some property values are promises, do .props().then(_)...}