53 lines
1.3 KiB
Plaintext
53 lines
1.3 KiB
Plaintext
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{{alias}}( collection, initial, reducer[, thisArg] )
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Applies a function against an accumulator and each element in a collection
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and returns the accumulated result, iterating from right to left.
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When invoked, the reduction function is provided four arguments:
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- `accumulator`: accumulated value
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- `value`: collection value
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- `index`: collection index
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- `collection`: the input collection
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If provided an empty collection, the function returns the initial value.
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Parameters
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----------
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collection: Array|TypedArray|Object
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Input collection. If provided an object, the object must be array-like
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(excluding strings and functions).
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initial: any
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Accumulator value used in the first invocation of the reduction
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function.
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reducer: Function
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Function to invoke for each element in the input collection.
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thisArg: any (optional)
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Execution context.
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Returns
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-------
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out: any
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Accumulated result.
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Examples
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--------
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> function sum( acc, v ) {
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... console.log( '%s: %d', acc, v );
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... return acc + v;
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... };
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> var arr = [ 1.0, 2.0, 3.0 ];
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> var out = {{alias}}( arr, 0, sum );
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2: 3.0
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1: 2.0
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0: 1.0
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> out
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6.0
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See Also
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--------
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