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{{alias}}( target, ...source )
Merges objects into a target object.
The target object is mutated.
Only plain objects are merged and extended. Other values/types are either
deep copied or assigned.
Support for deep merging class instances is inherently fragile.
`Number`, `String`, and `Boolean` objects are merged as primitives.
Functions are not deep copied.
Parameters
----------
target: Object
Target object.
source: ...Object
Source objects (i.e., objects to be merged into the target object).
Returns
-------
out: Object
Merged (target) object.
Examples
--------
> var target = { 'a': 'beep' };
> var source = { 'a': 'boop', 'b': 'bap' };
> var out = {{alias}}( target, source )
{ 'a': 'boop', 'b': 'bap' }
> var bool = ( out === target )
true
{{alias}}.factory( options )
Returns a function for merging and extending objects.
Parameters
----------
options: Object
Options.
options.level: integer (optional)
Merge level. Default: Infinity.
options.copy: boolean (optional)
Boolean indicating whether to deep copy merged values. Deep copying
prevents shared references and source object mutation. Default: true.
options.override: boolean|Function (optional)
Defines the merge strategy. If `true`, source object values will always
override target object values. If `false`, source values never override
target values (useful for adding, but not overwriting, properties). To
define a custom merge strategy, provide a function. Default: true.
options.extend: boolean (optional)
Boolean indicating whether new properties can be added to the target
object. If `false`, only shared properties are merged. Default: true.
Returns
-------
fcn: Function
Function which can be used to merge objects.
Examples
--------
> var opts = {
... 'level': 100,
... 'copy': true,
... 'override': true,
... 'extend': true
... };
> var merge = {{alias}}.factory( opts )
<Function>
// Set the `level` option to limit the merge depth:
> merge = {{alias}}.factory( { 'level': 2 } );
> var target = {
... '1': { 'a': 'beep', '2': { '3': null, 'b': [ 5, 6, 7 ] } }
... };
> var source = {
... '1': { 'b': 'boop', '2': { '3': [ 1, 2, 3 ] } }
... };
> var out = merge( target, source )
{ '1': { 'a': 'beep', 'b': 'boop', '2': { '3': [ 1, 2, 3 ] } } }
// Set the `copy` option to `false` to allow shared references:
> merge = {{alias}}.factory( { 'copy': false } );
> target = {};
> source = { 'a': [ 1, 2, 3 ] };
> out = merge( target, source );
> var bool = ( out.a === source.a )
true
// Set the `override` option to `false` to preserve existing properties:
> merge = {{alias}}.factory( { 'override': false } );
> target = { 'a': 'beep', 'b': 'boop' };
> source = { 'a': null, 'c': 'bop' };
> out = merge( target, source )
{ 'a': 'beep', 'b': 'boop', 'c': 'bop' }
// Define a custom merge strategy:
> function strategy( a, b, key ) {
... // a => target value
... // b => source value
... // key => object key
... if ( key === 'a' ) {
... return b;
... }
... if ( key === 'b' ) {
... return a;
... }
... return 'bebop';
... };
> merge = {{alias}}.factory( { 'override': strategy } );
> target = { 'a': 'beep', 'b': 'boop', 'c': 1234 };
> source = { 'a': null, 'b': {}, 'c': 'bop' };
> out = merge( target, source )
{ 'a': null, 'b': 'boop', 'c': 'bebop' }
// Prevent non-existent properties from being added to the target object:
> merge = {{alias}}.factory( { 'extend': false } );
> target = { 'a': 'beep', 'b': 'boop' };
> source = { 'b': 'hello', 'c': 'world' };
> out = merge( target, source )
{ 'a': 'beep', 'b': 'hello' }
See Also
--------
|
