Mapping out JSON structure

Question

I'm parsing a JSON message which looks something like:

{ 
    staff : [
       {name : 'John', department : 'Math'},
       {name : 'Sally', department : 'Science'},
    ],
    students : [
       {name : 'Bob', department : 'Law'},
       {name : 'Lisa', department : 'IT'}
    ]
}

From which I'd like to pull out an array of each separate value. i.e.

names -> ['John', 'Sally', 'Bob', 'Lisa']

At the moment I'm doing something like

var names = [];
msg.staff.forEach(function(e) { names.push(e.name) })
msg.students.forEach(function(e) { names.push(e.name)})

This feels overly verbose, just wondering if there's a cleaner way to approach this (for every attribute). I'm already including lodash in this project.

Answer 1

You can use _.pluck to get the value of a property of each object in an array:

_.pluck(obj.staff.concat(obj.students), 'name')

Answer 2

Your instinct is right; you don't need a mutable array to do this with lodash.

_(obj).map().flatten().pluck('name').value();

This version works for any number of array values in o.

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