deepdash

deepdash

tree traversal for lodash

Installation

In a browser load script after lodash:

<script src="lodash.js"></script>
<script src="deepdash.js"></script>

Using npm:

npm i --save deepdash

In Node.js:

//mixin new method into lodash object
const _ = require('deepdash')(require('lodash'));

Usage

let obj = {
  a: {
    b: {
      c: {
        d: [
          { i: 0 },
          { i: 1 },
          { i: 2 },
          { i: 3 },
          { i: 4 },
          { i: 5 },
          {
            o: {
              d: new Date(),
              f: function() {},
              skip: {
                please: {
                  dont: {
                    go: {
                      here: 'skip it',
                    },
                  },
                },
              },
            },
          },
        ],
        s: 'hello',
      },
      b: true,
    },
    n: 12345,
    u: undefined,
  },
  nl: null,
};
_.eachDeep(obj, (value, key, path, depth, parent, parentKey, parentPath) => {
  console.log(
    _.repeat('  ', depth) +
      key +
      ':' +
      (value === null ? 'null' : typeof value),
    parentPath && ' @' + parentPath
  );
  if(key=="skip"){
    return false;//return false explicitly to skip iteration over current value's children
  }
});

Console:

a:object
  b:object  @a
    c:object  @a.b
      d:object  @a.b.c
        0:object  @a.b.c.d
          i:number  @a.b.c.d[0]
        1:object  @a.b.c.d
          i:number  @a.b.c.d[1]
        2:object  @a.b.c.d
          i:number  @a.b.c.d[2]
        3:object  @a.b.c.d
          i:number  @a.b.c.d[3]
        4:object  @a.b.c.d
          i:number  @a.b.c.d[4]
        5:object  @a.b.c.d
          i:number  @a.b.c.d[5]
        6:object  @a.b.c.d
          o:object  @a.b.c.d[6]
            d:object  @a.b.c.d[6].o
            f:function  @a.b.c.d[6].o
            skip:object  @a.b.c.d[6].o
      s:string  @a.b.c
    b:boolean  @a.b
  n:number  @a
  u:undefined  @a
nl:null

Chaining works too:

  _(obj).eachDeep((value, key, path, depth, parent, parentKey, parentPath) => {/* do */}).value();

Methods

eachDeep (forEachDeep)

_.eachDeep(object, [iteratee=_.identity], [options={ track: false }])
Invokes given callback for each field and element of given object or array, nested too.

Arguments:

• object: (Object) The object to iterate over.
• [iteratee]: (Function) The function invoked per iteration. iteratee will be called with:
  • value, key, path, depth, parent, parentKey, parentPath, [parents]
• [options]: (Object)
  • [track]: (Boolean) track parents from current back to the root, useful for circular reference detecting. If true, iteratee will have additional parents object argument with values, keys and paths arrays inside.

Example:

  let circular = { a: { b: { c: {} } } };
  circular.a.b.c = circular;
  _.eachDeep(
    circular,
    (value, key, path, depth, parent, parentKey, parentPath, parents) => {
      if (_.indexOf(parents.values, value) !== -1) {
        console.log(
          "Circular reference skipped for '" + key + "' at " + parentPath
        );
        return false;
      }
      //do your things
    }
  ,{track:true});

Console:

  Circular reference skipped for 'c' at a.b

keysDeep (paths)

_.keysDeep(object, [iteratee=_.identity], [options={ checkCircular: false, includeCircularPath: true, leafsOnly: false }])
Creates an array of the paths of object or array.

Arguments:

• object: (Object) The object to iterate over.
• [options]: (Object)
  • [checkCircular]: (Boolean) check each value to not be one of the parents, to avoid circular references.
  • [includeCircularPath]: (Boolean) include path to circular reference, if found some, or skip it. Option ignored if checkCircular:false.
  • [leafsOnly]: (Boolean) return paths to childless values only. By default all the paths will be returned, including parents.

Example:

  let keys = _.keysDeep({
    a: {
      b: {
        c: [1, 2, 3],
        "hello world":{}
      },
    },
  });
  console.log(keys);
  keys = _.keysDeep({
    a: {
      b: {
        c: [1, 2, 3],
        "hello world":{}
      },
    },
  },{ leafsOnly: true });
  console.log(keys);

Console:

  [ 'a',
    'a.b',
    'a.b.c',
    'a.b.c[0]',
    'a.b.c[1]',
    'a.b.c[2]',
    'a.b["hello world"]' ]

  [
    'a.b.c[0]',
    'a.b.c[1]',
    'a.b.c[2]',
    'a.b["hello world"]' ]

Other traversal methods

Feel free to request other methods implementation.