lib/analytics.js
function pickPrefix(prefix, object) {
    var length = prefix.length;
    var sub;
    return foldl(
      function(acc, val, key) {
        if (key.substr(0, length) === prefix) {
          sub = key.substr(length);
          acc[sub] = val;
        }
        return acc;
      },
      {},
      object
    );
  }
function pickPrefix(prefix, object) {
    var length = prefix.length;
    var sub;
    return foldl(
      function(acc, val, key) {
        if (key.substr(0, length) === prefix) {
          sub = key.substr(length);
          acc[sub] = val;
        }
        return acc;
      },
      {},
      object
    );
  }
function pickPrefix ( prefix , object ) { var length = prefix . length ; var sub ; return foldl ( function ( acc , val , key ) { if ( key . substr ( 0 , length ) === prefix ) { sub = key . substr ( length ) ; acc [ sub ] = val ; } return acc ; } , { } , object ) ; }
Create a shallow copy of an input object containing only the properties
whose keys are specified by a prefix, stripped of that prefix

@param {String} prefix
@param {Object} object
@return {Object}
@api private
Create a shallow copy of an input object containing only the properties whose keys are specified by a prefix stripped of that prefix