kingjs/linq.last-or-undefined
@Returns the last element of a sequence that satisfies a specified condition or a undefined.
Usage
Return the last value of 0
, 1
, 2
like this;
var lastOrUndefined = require('@kingjs/linq.last-or-undefined');
var sequence = require('@kingjs/enumerable.create');
lastOrUndefined.call(sequence(0, 1, 2));
result:
2
Return the last odd value of 0
, 1
, 2
, 3
, 4
like this;
var lastOrUndefined = require('@kingjs/linq.last-or-undefined');
var sequence = require('@kingjs/enumerable.create');
var isOdd = function(x) { return x % 2 == 1; }
lastOrUndefined.call(sequence(0, 1, 2, 3, 4), isOdd);
result:
3
API
declare function lastOrUndefined(
this: Enumerable,
predicate?: (x) => boolean
)
Interfaces
-
Enumerable
: See @kingjs/enumerable.define.
Parameters
-
this
: The sequence of which last element is returned. -
predicate
: Optional predicate element must satisfy.
Return Value
Last element in the sequence or undefined if sequence is empty. If a predicate is provided, then the last element to match the predicate else undefined if no element satisfies the predicate.
Install
With npm installed, run
$ npm install @kingjs/linq.last-or-undefined
Acknowledgments
Like Enumerable.LastOrDefault
.
License
MIT