Filtering object properties based on value

Question

Is there some elegant way of filtering out falsey properties from this object with lodash/underscore? Similar to how _.compact(array) removes falsey elements fr

Answer 1

Prior to Lodash 4.0

You want _.pick, it takes a function as an argument and returns an object only containing the keys for which that function returns truthy. So you can do:

filtered = _.pick(obj, function(value, key) {return value;})

Or even more succinctly:

filtered = _.pick(obj, _.identity)

Lodash 4.0

Lodash 4.0 split the _.pick function into _.pick, which takes an array of properties, and _.pickBy which takes a function. So now it'd be

filtered = _.pickBy(obj, function(value, key) {return value;})

Or, since _.pickBy defaults to using _.identity as it's second argument, it can just be written as:

filtered = _.pickBy(obj);