Method ScanRight

ScanRight<TSource>(IEnumerable<TSource>, Func<TSource, TSource, TSource>)

Performs a right-associative scan (inclusive prefix) on a sequence of elements. This operator is the right-associative version of the Scan<TSource>(IEnumerable<TSource>, Func<TSource, TSource, TSource>) LINQ operator.

Declaration

public static IEnumerable<TSource> ScanRight<TSource>(this IEnumerable<TSource> source, Func<TSource, TSource, TSource> func)

Parameters

Type	Name	Description
IEnumerable<TSource>	source	Source sequence.
Func<TSource, TSource, TSource>	func	A right-associative accumulator function to be invoked on each element. Its first argument is the current value in the sequence; second argument is the previous accumulator value.

Returns

Type	Description
IEnumerable<TSource>	The scanned sequence.

Type Parameters

Name	Description
TSource	Type of elements in source sequence.

Remarks

This method is implemented by using deferred execution. However, source will be consumed in it's entirety immediately when first element of the returned sequence is consumed.

Examples

The following code example demonstrates how to execute a right-associative post-fix scan on a sequence using ScanRight.

var sequence = Enumerable.Range(1, 5)
    .Select(x => x.ToString());

// execute a scan of the sequence
var result = sequence
    .ScanRight((a, b) => $"({a}+{b})");

Console.WriteLine(
    "[ \"" +
    string.Join("\", \"", result) +
    "\" ]");

// This code produces the following output:
// [ "(1+(2+(3+(4+5))))", "(2+(3+(4+5)))", "(3+(4+5))", "(4+5)", "5" ]

Exceptions

Type	Condition
ArgumentNullException	source or func is null.

ScanRight<TSource, TAccumulate>(IEnumerable<TSource>, TAccumulate, Func<TSource, TAccumulate, TAccumulate>)

Performs a right-associative scan (inclusive prefix) on a sequence of elements. This operator is the right-associative version of the Scan<TSource>(IEnumerable<TSource>, Func<TSource, TSource, TSource>) LINQ operator.

Declaration

public static IEnumerable<TAccumulate> ScanRight<TSource, TAccumulate>(this IEnumerable<TSource> source, TAccumulate seed, Func<TSource, TAccumulate, TAccumulate> func)

Parameters

Type	Name	Description
IEnumerable<TSource>	source	Source sequence.
TAccumulate	seed	The initial accumulator value.
Func<TSource, TAccumulate, TAccumulate>	func	A right-associative accumulator function to be invoked on each element. Its first argument is the current value in the sequence; second argument is the previous accumulator value.

Returns

Type	Description
IEnumerable<TAccumulate>	The scanned sequence.

Type Parameters

Name	Description
TSource	Type of elements in source sequence.
TAccumulate	Type of the state accumulator.

Remarks

This method is implemented by using deferred execution. However, source will be consumed in it's entirety immediately when first element of the returned sequence is consumed.

Examples

The following code example demonstrates how to execute a right-associative post-fix scan on a sequence using ScanRight.

var sequence = Enumerable.Range(1, 5);

// execute a scan of the sequence
var result = sequence
    .ScanRight(
        "6",
        (a, b) => $"({a}+{b})");

Console.WriteLine(
    "[ \"" +
    string.Join("\", \"", result) +
    "\" ]");

// This code produces the following output:
// [ "(1+(2+(3+(4+(5+6)))))", "(2+(3+(4+(5+6))))", "(3+(4+(5+6)))", "(4+(5+6))", "(5+6)", "6" ]

Exceptions

Type	Condition
ArgumentNullException	source or func is null.