Method From

From<T>(Func<T>)

Returns a single-element sequence containing the result of invoking the function.

Declaration

public static IEnumerable<T> From<T>(Func<T> function)

Parameters

Type	Name	Description
Func<T>	function	The function to evaluate.

Returns

Type	Description
IEnumerable<T>	A sequence with the value resulting from invoking function.

Type Parameters

Name	Description
T	The type of the object returned by the function.

Remarks

This operator uses deferred execution and streams the results. If the resulting sequence is enumerated multiple times, the function will be invoked multiple times too.

Examples

The following code example demonstrates how to project a sequence of functions into their return values using From.

int Func1() => 3;

// Execute an action for each element
var result = SuperEnumerable
    .From(Func1);

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

// This code produces the following output:
// [3]

Exceptions

Type	Condition
ArgumentNullException	function is null.

From<T>(Func<T>, Func<T>)

Returns a sequence containing the result of invoking each parameter function in order.

Declaration

public static IEnumerable<T> From<T>(Func<T> function1, Func<T> function2)

Parameters

Type	Name	Description
Func<T>	function1	The first function to evaluate.
Func<T>	function2	The second function to evaluate.

Returns

Type	Description
IEnumerable<T>	A sequence with the values resulting from invoking function1 and function2.

Type Parameters

Name	Description
T	The type of the object returned by the functions.

Remarks

This operator uses deferred execution and streams the results. If the resulting sequence is enumerated multiple times, the functions will be invoked multiple times too.

Examples

The following code example demonstrates how to project a sequence of functions into their return values using From.

int Func1() => 3;
int Func2() => 5;

// Execute an action for each element
var result = SuperEnumerable
    .From(Func1, Func2);

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

// This code produces the following output:
// [3, 5]

Exceptions

Type	Condition
ArgumentNullException	function1 or function2 is null.

From<T>(Func<T>, Func<T>, Func<T>)

Returns a sequence containing the result of invoking each parameter function in order.

Declaration

public static IEnumerable<T> From<T>(Func<T> function1, Func<T> function2, Func<T> function3)

Parameters

Type	Name	Description
Func<T>	function1	The first function to evaluate.
Func<T>	function2	The second function to evaluate.
Func<T>	function3	The third function to evaluate.

Returns

Type	Description
IEnumerable<T>	A sequence with the values resulting from invoking function1, function2 and function3.

Type Parameters

Name	Description
T	The type of the object returned by the functions.

Remarks

This operator uses deferred execution and streams the results. If the resulting sequence is enumerated multiple times, the functions will be invoked multiple times too.

Examples

The following code example demonstrates how to project a sequence of functions into their return values using From.

int Func1() => 3;
int Func2() => 5;
int Func3() => 1;

// Execute an action for each element
var result = SuperEnumerable
    .From(Func1, Func2, Func3);

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

// This code produces the following output:
// [3, 5, 1]

Exceptions

Type	Condition
ArgumentNullException	function1, function2, or function3 is null.

From<T>(params Func<T>[])

Returns a sequence containing the values resulting from invoking (in order) each function in the source sequence of functions.

Declaration

public static IEnumerable<T> From<T>(params Func<T>[] functions)

Parameters

Type	Name	Description
Func<T>[]	functions	The functions to evaluate.

Returns

Type	Description
IEnumerable<T>	A sequence with the values resulting from invoking all of the functions.

Type Parameters

Name	Description
T	The type of the object returned by the functions.

Remarks

This operator uses deferred execution and streams the results. If the resulting sequence is enumerated multiple times, the functions will be invoked multiple times too.

Examples

The following code example demonstrates how to project a sequence of functions into their return values using From.

int Func1() => 3;
int Func2() => 5;
int Func3() => 1;
int Func4() => 7;

// Execute an action for each element
var result = SuperEnumerable
    .From(Func1, Func2, Func3, Func4);

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

// This code produces the following output:
// [3, 5, 1, 7]

Exceptions

Type	Condition
ArgumentNullException	functions is null.