mergee

Utilities for objects

This is a selection of utilities for objects and contains:

• assign - assigns multiple sources to a target object
• extend - (same as assign) extends a target object with multiple sources
• merge - merge multiple sources into a target object
• mergeExt - same as merge but with options
• clone - deep clone of an object or array.
• pick - pick properties from an object
• omit - omit properties from an object
• select - select properties from an object
• isCircular - check object for circular structures
• deepEqual - deep comparison

Table of Contents

• Methods
  • assign(target, source)
  • extend(target, source)
  • merge(target, source)
  • mergeExt(opts, opts.ignoreNull, opts.ignoreCircular, target, source)
  • clone(obj)
  • pick(obj, props)
  • omit(obj, props)
  • get(obj, keys)
  • set(obj, keys, value)
  • isCircular(obj)
  • deepEqual(actual, expected)
• Contribution and License Agreement
• License

Methods

assign(target, source)

assign multiple source objects to object target

Example

var assign  = require('mergee').assign,
    target  = { a:{A:1}, b:{A:1} },
    source1 = { b:{B:2}, c:{B:2} },
    source2 = { d:{C:3} };
assign(target, source1, source2);
// target === { a:{A:1}, b:{B:2}, c:{B:2}, d:{C:3} };

Parameters

target: Object | Array | function, assign multiple source objects to object target

Example

var assign  = require('mergee').assign,
    target  = { a:{A:1}, b:{A:1} },
    source1 = { b:{B:2}, c:{B:2} },
    source2 = { d:{C:3} };
assign(target, source1, source2);
// target === { a:{A:1}, b:{B:2}, c:{B:2}, d:{C:3} };

source: Any, arguments 2 ... n

Returns: Object, assigned target

extend(target, source)

Same as assign.

extend object target with multiple source objects

Example

var extend  = require('mergee').extend,
    target  = { a:{A:1}, b:{A:1} },
    source1 = { b:{B:2}, c:{B:2} },
    source2 = { d:{C:3} };
extend(target, source1, source2);
// target === { a:{A:1}, b:{B:2}, c:{B:2}, d:{C:3} };

Parameters

target: Object | Array | function, extend object target with multiple source objects

Example

var extend  = require('mergee').extend,
    target  = { a:{A:1}, b:{A:1} },
    source1 = { b:{B:2}, c:{B:2} },
    source2 = { d:{C:3} };
extend(target, source1, source2);
// target === { a:{A:1}, b:{B:2}, c:{B:2}, d:{C:3} };

source: Any, arguments 2 ... n

Returns: Object, extended target

merge(target, source)

merge multiple objects into target

Example

var merge = require('mergee').merge,
    target  = { t: 1, x: { y: 'z' } },
    source1 = { t: { s1: /source1/ } },
    source2 = { t: { s2: new Date(100), x: null } };
merge(target, source1, source2);
// target === { t: { s1: /source1/, s2: Wed Dec 31 1969 17:00:00 GMT-0700 (MST) }, x: null }

Parameters

target: Object | function | Array, target object

source: Any, arguments 2 ... n

Returns: Object, merged target

mergeExt(opts, opts.ignoreNull, opts.ignoreCircular, target, source)

extended merge

Example

var merge = require('mergee').merge,
    target  = { t: 1, x: { y: 'z' } },
    source1 = { t: { s1: /source1/ } },
    source2 = { t: { s2: new Date(100), x: null } };
mergeExt({ ignoreNull: true }, target, source1, source2);
// target === { t: { s1: /source1/, s2: Wed Dec 31 1969 17:00:00 GMT-0700 (MST) }, x: { y: 'z' } }

Parameters

opts: Object, options

opts.ignoreNull: Boolean, treat source === null as undefined - target does not get deleted

opts.ignoreCircular: Boolean, ignore cirular structures - no error gets thrown

target: Object | function | Array, target object

source: Any, arguments 3 ... n

Returns: Object, merged target

clone(obj)

perform a deep clone of obj

Example

var clone = require('mergee').clone,
    obj = { a: { b: { c: 1 } } };
var cloned = clone(obj);
// (cloned !== obj)
// (cloned.a !== obj.a)
// (cloned.a.b !== obj.a.b)

Parameters

obj: Object | Array, object to get cloned

Returns: Object | Array, deep cloned object

pick(obj, props)

pick properties from obj into a new object

Example

var r,
    pick = require('mergee').pick,
    obj = { a: 1, b: [ 1, 2 ], c: { cc:3, 'c-d':4 }, '0d': { '0d0': 5 } };
r = pick(obj, ['a', 'b[1]', 'c["c-d"]', '0d.0d0']);
//> r = { a: 1, b: { '1': 2 }, c: { 'c-d': 4 }, '0d': { '0d0': 5 } }
r = pick(obj, 'a, b[1], c["c-d"], 0d.0d0');
//> r = { a: 1, b: { '1': 2 }, c: { 'c-d': 4 }, '0d': { '0d0': 5 } }

Parameters

obj: Object, object to pick properties from

props: Array | String, Array of properties or comma separated string of properties

Returns: Object, object with picked properties

omit(obj, props)

omit properties from obj into a new object

Example

var r,
    omit = require('mergee').omit,
    obj = { a: 1, b: [ 1, 2 ], c: { cc:3, 'c-d':4 }, '0d': { '0d0': 5 } };
r = omit(obj, ['a', 'b[1]', 'c["c-d"]', '0d.0d0']);
// r = { b: [ 1,  ], c: { cc: 3 }, '0d': {} }
r = omit(obj, 'a, b[1], c["c-d"], 0d.0d0');
// r = { b: [ 1,  ], c: { cc: 3 }, '0d': {} }

Parameters

obj: Object, object

props: Array | String, Array of properties or comma separated string of properties

Returns: Object, object with omitted properties

get(obj, keys)

get properties from obj

Example

var r,
    get = require('mergee').get,
    obj = { a: { b: { c: 1 } } };
r = get(obj, ['a', 'b', 'c']);
// r = 1
r = get(obj, 'a.b');
// r = { c: 1 }
r = get(obj, 'there.is.no.such.property'); // this will not throw!
// r = undefined

Parameters

obj: Object, object to select from

keys: Array | String, Array of properties or dot separated string of properties; If using a String avoid using property names containing a .

Returns: Object, selected object

set(obj, keys, value)

set a property in obj

Example

var r,
    set = require('mergee').set,
    obj = {};
r = set(obj, ['a', 'b'], { c:1 });
//> r = { a: { b: { c: 1 } } }
r = set(obj, 'a.b.d', 2);
//> r = { a: { b: { c:1, d:2 } } }

Parameters

obj: Object, object to select from

keys: Array | String, Array of properties or dot separated string of properties; If using a String avoid using property names containing a .

value: Any, The value to set

Returns: Object, set object

isCircular(obj)

check if an object obj contains circular structures

Example

var isCircular  = require('mergee').isCircular,
    obj = { a: {} };
obj.a.c = { c: 1 };
// isCircular(obj) === true

Parameters

obj: Object, Object to check

Returns: Boolean, true if obj contains circularities

deepEqual(actual, expected)

deep comparison of actual and expected

Parameters

actual: Any, deep comparison of actual and expected

expected: Any, deep comparison of actual and expected

Returns: Boolean, true if actual equals expected

Contribution and License Agreement

If you contribute code to this project, you are implicitly allowing your code to be distributed under the MIT license. You are also implicitly verifying that all code is your original work or correctly attributed with the source of its origin and licence.

License

This module contains code from other MIT licensed sources:

• lib/deepequal.js is from node v0.12 assert.js - MIT licensed
• lib/util.js is from node v0.12 util.js - MIT licensed

Copyright (c) 2015 commenthol (MIT License)

See LICENSE for more info.