javascript - What is this function used for?

Question

Looking at the official website of underscore, it seems that the usage is different

Answer 1

_.omit()Receives attribute names or functions as rules to filter out attributes in objects.

The literal meaning here is to filter out the attributes whose property values ​​are inverted to be true, that is: 0, undefined, null, etc.

For example:

_.omit({foo:0,bar:null,baz:1},function(v){return !v})
// {bar:1}