deepdash

Deepdash

Looking for eachDeep, filterDeep, omitDeep, keysDeep etc? Tree traversal extension for Lodash.

Installation

In a browser load script after Lodash:

<script src="https://cdn.jsdelivr.net/npm/lodash/lodash.min.js"></script>
<script src="https://cdn.jsdelivr.net/npm/deepdash/deepdash.min.js"></script>

Using npm:

npm i --save deepdash

In Node.js (same for the Angular component):

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

Or as ECMAScript Module:

import lodash from "lodash";
import deepdash from "deepdash";
const _ = deepdash(lodash);

Methods

eachDeep(forEachDeep) - iterate over all the children and sub-children (📚 docs)

Example

children example collection is here

  let children = [/* ... */];
  function displayField(val, key, parent, context) {
      if (_.isArray(parent)) {
        key = '[' + key + ']';
      }
      console.log(
        _.repeat('   ', context.depth) +
          '→ ' +
          key +
          ': ' +
          (_.isArray(val)
            ? '[' + val.length + ']'
            : _.isObject(val)
            ? '{' + (val.name || '') + '}'
            : val)
      );
    }

    console.log('\n = Iterate over tree (each child object) = \n');

    _.eachDeep(children, displayField, { tree: true });

    console.log('\n = Iterate over object (each field) = \n');

    _.eachDeep(children, displayField);

Console:

 = Iterate over tree (each child object) =

→ [0]: {node 1}
      → [0]: {node 1.1}
      → [1]: {node 1.2}
      → [2]: {node 1.3}
→ [1]: {node 2}
      → [0]: {node 2.1}
      → [1]: {node 2.2}
      → [2]: {node 2.3}
→ [2]: {node 3}
      → [0]: {node 3.1}
      → [1]: {node 3.2}
      → [2]: {node 3.3}

 = Iterate over object (each field) =

→ [0]: {node 1}
   → description: description for node 1
   → comment: comment for node 1
   → note: note for node 1
   → name: node 1
   → bad: false
   → children: [3]
      → [0]: {node 1.1}
         → description: description for node 1.1
         → comment: comment for node 1.1
         → note: note for node 1.1
         → name: node 1.1
         → bad: false
      → [1]: {node 1.2}
         → description: description for node 1.2
         → comment: comment for node 1.2
         → note: note for node 1.2
         → name: node 1.2
         → good: true
      → [2]: {node 1.3}
         → description: description for node 1.3
         → comment: comment for node 1.3
         → note: note for node 1.3
         → name: node 1.3
         → bad: true
         → good: false
→ [1]: {node 2}
   → description: description for node 2
   → comment: comment for node 2
   → note: note for node 2
   → name: node 2
   → good: true
   → children: [3]
      → [0]: {node 2.1}
         → description: description for node 2.1
         → comment: comment for node 2.1
         → note: note for node 2.1
         → name: node 2.1
         → bad: false
      → [1]: {node 2.2}
         → description: description for node 2.2
         → comment: comment for node 2.2
         → note: note for node 2.2
         → name: node 2.2
         → good: true
      → [2]: {node 2.3}
         → description: description for node 2.3
         → comment: comment for node 2.3
         → note: note for node 2.3
         → name: node 2.3
         → bad: true
         → good: false
→ [2]: {node 3}
   → description: description for node 3
   → comment: comment for node 3
   → note: note for node 3
   → name: node 3
   → bad: true
   → good: false
   → children: [3]
      → [0]: {node 3.1}
         → description: description for node 3.1
         → comment: comment for node 3.1
         → note: note for node 3.1
         → name: node 3.1
         → bad: false
      → [1]: {node 3.2}
         → description: description for node 3.2
         → comment: comment for node 3.2
         → note: note for node 3.2
         → name: node 3.2
         → good: true
      → [2]: {node 3.3}
         → description: description for node 3.3
         → comment: comment for node 3.3
         → note: note for node 3.3
         → name: node 3.3
         → bad: true
         → good: false

filterDeep - deep filter object (📚 docs)

Example

children example collection is here

  let children = [/* ... */];
  console.log('\n = Filter tree (good children) = \n');

  console.log(
    _.filterDeep(children, 'good', { tree: true })
  );

  console.log('\n = Filter object (names of good children) = \n');

  console.log(
      _.filterDeep(children, (val, key, parent) => {
        if (key == 'name' && parent.good) return true;
      })
  );

Console:

 = Filter tree (good children) =

[
  {
    "description": "description for node 1",
    "comment": "comment for node 1",
    "note": "note for node 1",
    "name": "node 1",
    "bad": false,
    "children": [
      {
        "description": "description for node 1.2",
        "comment": "comment for node 1.2",
        "note": "note for node 1.2",
        "name": "node 1.2",
        "good": true
      }
    ]
  },
  {
    "description": "description for node 2",
    "comment": "comment for node 2",
    "note": "note for node 2",
    "name": "node 2",
    "good": true,
    "children": [
      {
        "description": "description for node 2.2",
        "comment": "comment for node 2.2",
        "note": "note for node 2.2",
        "name": "node 2.2",
        "good": true
      }
    ]
  },
  {
    "description": "description for node 3",
    "comment": "comment for node 3",
    "note": "note for node 3",
    "name": "node 3",
    "bad": true,
    "good": false,
    "children": [
      {
        "description": "description for node 3.2",
        "comment": "comment for node 3.2",
        "note": "note for node 3.2",
        "name": "node 3.2",
        "good": true
      }
    ]
  }
]

 = Filter object (names of good children) =

[
  {
    "children": [
      {
        "name": "node 1.2"
      }
    ]
  },
  {
    "name": "node 2",
    "children": [
      {
        "name": "node 2.2"
      }
    ]
  },
  {
    "children": [
      {
        "name": "node 3.2"
      }
    ]
  }
]

pickDeep - get object only with keys specified by names or regexes (📚 docs)

Example

children example collection is here

  let children = [/* ... */];
  console.log('\n = Pick name and description only = \n');

  console.log(
    _.pickDeep(children, ['name', 'description'])
  );

Console:

 = Pick name and description only =

[
  {
    "description": "description for node 1",
    "name": "node 1",
    "children": [
      {
        "description": "description for node 1.1",
        "name": "node 1.1"
      },
      {
        "description": "description for node 1.2",
        "name": "node 1.2"
      },
      {
        "description": "description for node 1.3",
        "name": "node 1.3"
      }
    ]
  },
  {
    "description": "description for node 2",
    "name": "node 2",
    "children": [
      {
        "description": "description for node 2.1",
        "name": "node 2.1"
      },
      {
        "description": "description for node 2.2",
        "name": "node 2.2"
      },
      {
        "description": "description for node 2.3",
        "name": "node 2.3"
      }
    ]
  },
  {
    "description": "description for node 3",
    "name": "node 3",
    "children": [
      {
        "description": "description for node 3.1",
        "name": "node 3.1"
      },
      {
        "description": "description for node 3.2",
        "name": "node 3.2"
      },
      {
        "description": "description for node 3.3",
        "name": "node 3.3"
      }
    ]
  }
]

omitDeep - get object without keys specified by names or regexes (📚 docs)

Example

children example collection is here

  let children = [/* ... */];
  console.log('\n = Omit paths not ending with "e" = \n');

  console.log(
    _.omitDeep(children, /[^e]$/i, { onMatch: { skipChildren: false } }),
  );

Console:

 = Omit paths not ending with "e" =

[
  {
    "note": "note for node 1",
    "name": "node 1",
    "children": [
      {
        "note": "note for node 1.1",
        "name": "node 1.1"
      },
      {
        "note": "note for node 1.2",
        "name": "node 1.2"
      },
      {
        "note": "note for node 1.3",
        "name": "node 1.3"
      }
    ]
  },
  {
    "note": "note for node 2",
    "name": "node 2",
    "children": [
      {
        "note": "note for node 2.1",
        "name": "node 2.1"
      },
      {
        "note": "note for node 2.2",
        "name": "node 2.2"
      },
      {
        "note": "note for node 2.3",
        "name": "node 2.3"
      }
    ]
  },
  {
    "note": "note for node 3",
    "name": "node 3",
    "children": [
      {
        "note": "note for node 3.1",
        "name": "node 3.1"
      },
      {
        "note": "note for node 3.2",
        "name": "node 3.2"
      },
      {
        "note": "note for node 3.3",
        "name": "node 3.3"
      }
    ]
  }
]

indexate - get an object with all the paths as keys and corresponding values (📚 docs)

Example

  let index = _.indexate(
    {
      a: {
        b: {
          c: [1, 2, 3],
          'hello world': {},
        },
      },
    },
    { leavesOnly: true }
  );
  console.log(index);

Console:

{ 'a.b.c[0]': 1,
  'a.b.c[1]': 2,
  'a.b.c[2]': 3,
  'a.b["hello world"]': {} }

paths(keysDeep) - get an array of paths (📚 docs)

Example

  let paths = _.paths(
    {
      a: {
        b: {
          c: [1, 2, 3],
          'hello world': {},
        },
      },
    },
    { leavesOnly: false }
  );
  console.log(paths);

Console:

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

condense - condense sparse array (📚 docs)

Example

  let arr = ['a', 'b', 'c', 'd', 'e'];
  delete arr[1];
  console.log(arr);
  delete arr[3];
  console.log(arr);
  _.condense(arr);
  console.log(arr);

Console:

  [ 'a', <1 empty item>, 'c', 'd', 'e' ]
  [ 'a', <1 empty item>, 'c', <1 empty item>, 'e' ]
  [ 'a', 'c', 'e' ]

condenseDeep - condense all the nested arrays (📚 docs)

Example

  let obj = { arr: ['a', 'b', { c: [1, , 2, , 3] }, 'd', 'e'] };
  delete obj.arr[1];
  delete obj.arr[3];
  _.condenseDeep(obj);
  console.log(obj);

Console:

  { arr: [ 'a', { c: [ 1, 2, 3 ] }, 'e' ] }

exists - like a _.has but returns false for empty array slots (📚 docs)

Example

  var obj = [, { a: [, 'b'] }];
  console.log(_.exists(obj, 0)); // false
  console.log(_.exists(obj, 1)); // true
  console.log(_.exists(obj, '[1].a[0]')); // false
  console.log(_.exists(obj, '[1].a[1]')); // true

pathToString - convert an array to string path (opposite to _.toPath) (📚 docs)

Example

  console.log(_.pathToString(['a', 'b', 'c', 'defg', 0, '1', 2.3]));
  // a.b.c.defg[0][1]["2.3"]
  console.log(_.pathToString(['"', '"', '"']));
  // ["\\""]["\\""]["\\""]
  console.log(_.pathToString('it.s.a.string'));
  // it.s.a.string

Example Collection

'children' object used in examples above

let children = [
  {
    description: 'description for node 1',
    comment: 'comment for node 1',
    note: 'note for node 1',
    name: 'node 1',
    bad: false,
    children: [
      {
        description: 'description for node 1.1',
        comment: 'comment for node 1.1',
        note: 'note for node 1.1',
        name: 'node 1.1',
        bad: false,
      },
      {
        description: 'description for node 1.2',
        comment: 'comment for node 1.2',
        note: 'note for node 1.2',
        name: 'node 1.2',
        good: true,
      },
      {
        description: 'description for node 1.3',
        comment: 'comment for node 1.3',
        note: 'note for node 1.3',
        name: 'node 1.3',
        bad: true,
        good: false,
      },
    ],
  },
  {
    description: 'description for node 2',
    comment: 'comment for node 2',
    note: 'note for node 2',
    name: 'node 2',
    good: true,
    children: [
      {
        description: 'description for node 2.1',
        comment: 'comment for node 2.1',
        note: 'note for node 2.1',
        name: 'node 2.1',
        bad: false,
      },
      {
        description: 'description for node 2.2',
        comment: 'comment for node 2.2',
        note: 'note for node 2.2',
        name: 'node 2.2',
        good: true,
      },
      {
        description: 'description for node 2.3',
        comment: 'comment for node 2.3',
        note: 'note for node 2.3',
        name: 'node 2.3',
        bad: true,
        good: false,
      },
    ],
  },
  {
    description: 'description for node 3',
    comment: 'comment for node 3',
    note: 'note for node 3',
    name: 'node 3',
    bad: true,
    good: false,
    children: [
      {
        description: 'description for node 3.1',
        comment: 'comment for node 3.1',
        note: 'note for node 3.1',
        name: 'node 3.1',
        bad: false,
      },
      {
        description: 'description for node 3.2',
        comment: 'comment for node 3.2',
        note: 'note for node 3.2',
        name: 'node 3.2',
        good: true,
      },
      {
        description: 'description for node 3.3',
        comment: 'comment for node 3.3',
        note: 'note for node 3.3',
        name: 'node 3.3',
        bad: true,
        good: false,
      },
    ],
  },
];

See full docs for details.