System.Linq.AsyncEnumerable

Provides a set of static methods for querying objects that implement .

Applies an accumulator function over a sequence.

The type of the elements of source. An to aggregate over. An accumulator function to be invoked on each element. The to monitor for cancellation requests. The default is . The final accumulator value. is . is . contains no elements.

Applies an accumulator function over a sequence.

Applies an accumulator function over a sequence. The specified seed value is used as the initial accumulator value.

The type of the elements of source. The type of the accumulator value. An to aggregate over. The initial accumulator value. An accumulator function to be invoked on each element. The to monitor for cancellation requests. The default is . The final accumulator value. is . is .

Applies an accumulator function over a sequence. The specified seed value is used as the initial accumulator value.

Applies an accumulator function over a sequence. The specified seed value is used as the initial accumulator value, and the specified function is used to select the result value.

The type of the elements of source. The type of the accumulator value. The type of the resulting value. An to aggregate over. The initial accumulator value. An accumulator function to be invoked on each element. A function to transform the final accumulator value into the result value. The to monitor for cancellation requests. The default is . The transformed final accumulator value. is . is . is .

Applies an accumulator function over a sequence. The specified seed value is used as the initial accumulator value, and the specified function is used to select the result value.

Applies an accumulator function over a sequence, grouping results by key.

The type of the elements of . The type of the key returned by . The type of the accumulator value. An to aggregate over. A function to extract the key for each element. The initial accumulator value. An accumulator function to be invoked on each element. An to compare keys with. An enumerable containing the aggregates corresponding to each key deriving from . This method is comparable to the GroupBy methods where each grouping is being aggregated into a single value as opposed to allocating a collection for each group. is . is . is .

Applies an accumulator function over a sequence, grouping results by key.

The type of the elements of . The type of the key returned by . The type of the accumulator value. An to aggregate over. A function to extract the key for each element. A factory for the initial accumulator value. An accumulator function to be invoked on each element. An to compare keys with. An enumerable containing the aggregates corresponding to each key deriving from . This method is comparable to the GroupBy methods where each grouping is being aggregated into a single value as opposed to allocating a collection for each group. is . is . is . is .

Applies an accumulator function over a sequence, grouping results by key.

Determines whether all elements of a sequence satisfy a condition.

The type of the elements of source. An that contains the elements to apply the predicate to. A function to test each element for a condition. The to monitor for cancellation requests. The default is . if every element of the source sequence passes the test in the specified predicate, or if the sequence is empty; otherwise, . is . is .

Determines whether all elements of a sequence satisfy a condition.

Determines whether a sequence contains any elements.

The type of the elements of source. The to check for emptiness. The to monitor for cancellation requests. The default is . if the source sequence contains any elements; otherwise, . is .

Determines whether any element of a sequence satisfies a condition.

An whose elements to apply the predicate to. A function to test each element for a condition. The to monitor for cancellation requests. The default is . if the source sequence is not empty and at least one of its elements passes the test in the specified predicate; otherwise, . is . is .

Determines whether any element of a sequence satisfies a condition.

Appends a value to the end of the sequence.

The type of the elements of source. A sequence of values. The value to append to source. A new sequence that ends with element. is .

Represents the insertion of one or more items before or after an .

The type of the source enumerable.

Represents the insertion of an item before or after an .

The type of the source enumerable.

Represents the insertion of multiple items before or after an .

The type of the source enumerable.

A base class for async enumerables that are loaded on-demand.

The type of each item to yield. The value of an async iterator is immutable; the operation it represents cannot be changed. However, an async iterator also serves as its own enumerator, so the state of an async iterator may change as it is being enumerated. Hence, state that is relevant to an async iterator's value should be kept in readonly fields. State that is relevant to an async iterator's enumeration (such as the currently yielded item) should be kept in non-readonly fields.

The item currently yielded by this iterator.

Makes a shallow copy of this iterator.

This method is called if is called more than once.

Puts this iterator in a state whereby no further enumeration will take place.

Derived classes should override this method if necessary to clean up any mutable state they hold onto (for example, calling DisposeAsync on other enumerators).

Gets the enumerator used to yield values from this iterator.

If is called for the first time on the same thread that created this iterator, the result will be this iterator. Otherwise, the result will be a shallow copy of this iterator.

Retrieves the next item in this iterator and yields it via .

true if there was another value to be yielded; otherwise, false.

Computes the average of a sequence of values.

A sequence of values to calculate the average of. The to monitor for cancellation requests. The default is . The average of the sequence of values. is . The sum of the elements in the sequence is larger than (via the returned task). contains no elements (via the returned task).

Computes the average of a sequence of values.

A sequence of values to calculate the average of. The to monitor for cancellation requests. The default is . The average of the sequence of values. is . contains no elements (via the returned task).

Computes the average of a sequence of values.

A sequence of values to calculate the average of. The to monitor for cancellation requests. The default is . The average of the sequence of values. is . contains no elements (via the returned task).

Computes the average of a sequence of values.

A sequence of values to calculate the average of. The to monitor for cancellation requests. The default is . The average of the sequence of values. is . contains no elements (via the returned task).

Computes the average of a sequence of nullable values.

A sequence of nullable values to calculate the average of. The to monitor for cancellation requests. The default is . The average of the sequence of values, or null if the source sequence is empty or contains only values that are null. is . The sum of the elements in the sequence is larger than (via the returned task). contains no elements (via the returned task).

Computes the average of a sequence of nullable values.

Casts the elements of an to the specified type.

The type to cast the elements of source to. The that contains the elements to be cast to type . An that contains each element of the source sequence cast to the type.

Split the elements of a sequence into chunks of size at most .

Every chunk except the last will be of size . The last chunk will contain the remaining elements and may be of a smaller size. The type of the elements of source. An whose elements to chunk. Maximum size of each chunk. An that contains the elements of the input sequence split into chunks of size . is . is less than 1.

Concatenates two sequences.

The type of the elements of the input sequences. The first sequence to concatenate. The sequence to concatenate to the first sequence. An that contains the concatenated elements of the two input sequences. is . is .

Represents the concatenation of two .

The type of the source enumerables.

The first source to concatenate.

The second source to concatenate.

Initializes a new instance of the class.

The first source to concatenate. The second source to concatenate.

Represents the concatenation of three or more .

The type of the source enumerables. To handle chains of >= 3 sources, we chain the iterators together and allow to fetch enumerables from the previous sources. This means that rather than each MoveNextAsync and Current calls having to traverse all of the previous sources, we only have to traverse all of the previous sources once per chained enumerable. An alternative would be to use an array to store all of the enumerables, but this has a much better memory profile and without much additional run-time cost.

The linked list of previous sources.

The source associated with this iterator.

The logical index associated with this iterator.

Initializes a new instance of the class.

The linked list of previous sources. The source associated with this iterator. The logical index associated with this iterator.

Represents the concatenation of two or more .

The type of the source enumerables.

The enumerator of the current source, if has been called.

Gets the enumerable at a logical index in this iterator. If the index is equal to the number of enumerables this iterator holds, null is returned.

The logical index.

Creates a new iterator that concatenates this iterator with an enumerable.

The next enumerable.

Determines whether a sequence contains a specified element.

The type of the elements of source. A sequence in which to locate a value. The value to locate in the sequence. An equality comparer to compare values. The to monitor for cancellation requests. The default is . if the source sequence contains an element that has the specified value; otherwise, . is .

Returns the number of elements in a sequence.

The type of the elements of source. A sequence that contains elements to be counted. The to monitor for cancellation requests. The default is . The number of elements in the input sequence. is . The number of elements in source is larger than (via the returned task).

Returns the number of elements in a sequence satisfy a condition.

The type of the elements of source. A sequence that contains elements to be tested and counted. A function to test each element for a condition. The to monitor for cancellation requests. The default is . The number of elements in the input sequence that satisfy the condition in the predicate function. is . The number of elements that satisfy the condition is larger than (via the returned task).

Returns the number of elements in a sequence satisfy a condition.

The type of the elements of source. A sequence that contains elements to be tested and counted. The to monitor for cancellation requests. The default is . The number of elements in the input sequence that satisfy the condition in the predicate function. is .

Returns the number of elements in a sequence satisfy a condition.

Returns the count of elements in the source sequence grouped by key.

The type of elements of . The type of the key returned by . A sequence that contains elements to be counted. A function to extract the key for each element. An to compare keys with. An enumerable containing the frequencies of each key occurrence in . is . is .

Returns the count of elements in the source sequence grouped by key.

Returns the elements of the specified sequence or the type parameter's default if the sequence is empty.

The type of the elements of source. The sequence to return a default value for if it is empty. An object that contains the default value for the TSource type if source is empty; otherwise, source. is .

Returns the elements of the specified sequence or the specified value if the sequence is empty.

The type of the elements of source. The sequence to return a default value for if it is empty. The value to return if the sequence is empty. An object that contains the default value for the TSource type if source is empty; otherwise, source. is .

Returns distinct elements from a sequence.

The sequence to remove duplicate elements from. An to compare values. An that contains distinct elements from the source sequence. is .

Returns distinct elements from a sequence according to a specified key selector function.

The type of the elements of . The type of key to distinguish elements by. The sequence to remove duplicate elements from. A function to extract the key for each element. An to compare keys. An that contains distinct elements from the source sequence. is . This method is implemented by using deferred execution. The immediate return value is an object that stores all the information that is required to perform the action. The query represented by this method is not executed until the object is enumerated either by calling its `GetEnumerator` method directly or by using `foreach` in Visual C# or `For Each` in Visual Basic. The method returns an unordered sequence that contains no duplicate values. If is , the default equality comparer, , is used to compare values. is . is .

Returns distinct elements from a sequence according to a specified key selector function.

Returns the element at a specified index in a sequence.

The type of the elements of source. An to return an element from. The index of the element to retrieve, which is either from the beginning or the end of the sequence. The to monitor for cancellation requests. The default is . The element at the specified position in the source sequence. is . is outside the bounds of the source sequence (via the returned task).

Returns the element at a specified index in a sequence, or a default value if the index is out of range.

The type of the elements of source. An to return an element from. The index of the element to retrieve, which is either from the beginning or the end of the sequence. The to monitor for cancellation requests. The default is . The default value of if is outside the bounds of the source sequence; otherwise, the element at the specified position in the source sequence. is .

Returns the element at a specified index in a sequence.

The type of the elements of . An to return an element from. The index of the element to retrieve, which is either from the start or the end. The token to monitor for cancellation requests. The default value is . is . is outside the bounds of the sequence. The element at the specified position in the sequence. If the type of implements , that implementation is used to obtain the element at the specified index. Otherwise, this method obtains the specified element. This method throws an exception if is out of range. To instead return a default value when the specified index is out of range, use the ElementAtOrDefaultAsync method. is . is outside the bounds of the source sequence (via the returned task).

Returns the element at a specified index in a sequence or a default value if the index is out of range.

The type of the elements of . An to return an element from. The index of the element to retrieve, which is either from the start or the end. The token to monitor for cancellation requests. The default value is . is . if is outside the bounds of the sequence; otherwise, the element at the specified position in the sequence. If the type of implements , that implementation is used to obtain the element at the specified index. Otherwise, this method obtains the specified element. The default value for reference and nullable types is . is .

Returns an empty that has the specified type argument.

The type of the elements of the sequence. An empty whose type argument is .

Determines whether is known to be an always-empty enumerable.

Produces the set difference of two sequences.

The type of the elements of the input sequences. An whose elements that are not also in second will be returned. An whose elements that also occur in the first sequence will cause those elements to be removed from the returned sequence. An to compare values. A sequence that contains the set difference of the elements of two sequences. is . is .

Produces the set difference of two sequences according to a specified key selector function.

The type of the elements of the input sequence. The type of key to identify elements by. An whose keys that are not also in will be returned. An whose keys that also occur in the first sequence will cause those elements to be removed from the returned sequence. A function to extract the key for each element. The to compare values. A sequence that contains the set difference of the elements of two sequences. is . is . is .

Produces the set difference of two sequences according to a specified key selector function.

Returns the first element of a sequence.

The type of the elements of source. The to return the first element of. The to monitor for cancellation requests. The default is . The first element in the specified sequence. is . The source sequence is empty (via the returned task).

Returns the first element in a sequence that satisfies a specified condition.

The type of the elements of source. An to return an element from. A function to test each element for a condition. The to monitor for cancellation requests. The default is . The first element in the sequence that passes the test in the specified predicate function. is . is . The source sequence is empty, or no element in the sequence satisfies the condition in predicate (via the returned task).

Returns the first element in a sequence that satisfies a specified condition.

Returns the first element of a sequence, or the default value of if the sequence contains no elements.

The type of the elements of . The to return the first element of. The to monitor for cancellation requests. The default is . The default value of if is empty; otherwise, the first element in . is .

Returns the first element of a sequence, or a default value if the sequence contains no elements.

The type of the elements of . The to return the first element of. The default value to return if the sequence is empty. The to monitor for cancellation requests. The default is . if is empty; otherwise, the first element in . is .

Returns the first element of the sequence that satisfies a condition or a default value if no such element is found.

An to return an element from. A function to test each element for a condition. The to monitor for cancellation requests. The default is . The default value of if source is empty or if no element passes the test specified by predicate; otherwise, the first element in source that passes the test specified by predicate. is . is .

Returns the first element of the sequence that satisfies a condition or a default value if no such element is found.

The type of the elements of . An to return an element from. A function to test each element for a condition. The default value to return if the sequence is empty. The to monitor for cancellation requests. The default is . if is empty or if no element passes the test specified by ; otherwise, the first element in that passes the test specified by . is . is .

Returns the first element of the sequence that satisfies a condition or a default value if no such element is found.

Groups the elements of a sequence according to a specified key selector function.

The type of the elements of source. The type of the key returned by . An of elements to group. A function to extract the key for each element. An to compare keys. An where each contains a sequence of objects and a key. is . is .

Groups the elements of a sequence according to a specified key selector function.

Groups the elements of a sequence according to a key selector function. The keys are compared by using a comparer and each group's elements are projected by using a specified function.

The type of the elements of source. The type of the key returned by . The type of the elements in the . An of elements to group. A function to extract the key for each element. A function to map each source element to an element in an . An to compare keys. An where each contains a sequence of objects of type and a key. is . is . is .

Groups the elements of a sequence according to a key selector function. The keys are compared by using a comparer and each group's elements are projected by using a specified function.

Groups the elements of a sequence according to a specified key selector function and creates a result value from each group and its key.

The type of the elements of source. The type of the key returned by . The type of the result value returned by resultSelector. An of elements to group. A function to extract the key for each element. A function to create a result value from each group. An to compare keys. A collection of elements of type where each element represents a projection over a group and its key. is . is . is .

Groups the elements of a sequence according to a specified key selector function and creates a result value from each group and its key.

Groups the elements of a sequence according to a specified key selector function and creates a result value from each group and its key. Key values are compared by using a specified comparer, and the elements of each group are projected by using a specified function.

The type of the elements of source. The type of the key returned by . The type of the elements in each . The type of the result value returned by . An of elements to group. A function to extract the key for each element. A function to map each source element to an element in an . A function to create a result value from each group. An to compare keys. A collection of elements of type where each element represents a projection over a group and its key. is . is . is . is .

Correlates the elements of two sequences based on key equality and groups the results.

The first sequence to join. The sequence to join to the first sequence. A function to extract the join key from each element of the first sequence. A function to extract the join key from each element of the second sequence. A function to create a result element from an element from the first sequence and a collection of matching elements from the second sequence. An to use to hash and compare keys. An that contains elements of type that are obtained by performing a grouped join on two sequences. is . is . is . is . is .

Correlates the elements of two sequences based on key equality and groups the results.

Returns an enumerable that incorporates the element's index into a tuple.

The type of the elements of . The source enumerable providing the elements. An enumerable that incorporates each element index into a tuple. is .

Produces the set intersection of two sequences.

The type of the elements of the input sequences. An whose distinct elements that also appear in second will be returned. An whose distinct elements that also appear in the first sequence will be returned. An to compare values. A sequence that contains the elements that form the set intersection of two sequences. is . is .

Produces the set intersection of two sequences according to a specified key selector function.

The type of the elements of the input sequences. The type of key to identify elements by. An whose distinct elements that also appear in will be returned. An whose distinct elements that also appear in the first sequence will be returned. A function to extract the key for each element. An to compare keys. A sequence that contains the elements that form the set intersection of two sequences. or is . This method is implemented by using deferred execution. The immediate return value is an object that stores all the information that is required to perform the action. The query represented by this method is not executed until the object is enumerated either by calling its `GetEnumerator` method directly or by using `foreach` in Visual C# or `For Each` in Visual Basic. The intersection of two sets A and B is defined as the set that contains all the elements of A that also appear in B, but no other elements. When the object returned by this method is enumerated, `Intersect` yields distinct elements occurring in both sequences in the order in which they appear in . If is , the default equality comparer, , is used to compare values. is . is . is .

Produces the set intersection of two sequences according to a specified key selector function.

Correlates the elements of two sequences based on matching keys.

The type of the elements of the first sequence. The type of the elements of the second sequence. The type of the keys returned by the key selector functions. The type of the result elements. The first sequence to join. The sequence to join to the first sequence. A function to extract the join key from each element of the first sequence. A function to extract the join key from each element of the second sequence. A function to create a result element from two matching elements. An to use to hash and compare keys. An that has elements of type that are obtained by performing an inner join on two sequences. is . is . is . is . is .

Correlates the elements of two sequences based on matching keys.

Returns the last element of a sequence.

The type of the elements of source. An to return the last element of. The to monitor for cancellation requests. The default is . The value at the last position in the source sequence. is . The source sequence is empty (via the returned task).

Returns the last element of a sequence that satisfies a specified condition.

The type of the elements of source. An to return an element from. A function to test each element for a condition. The to monitor for cancellation requests. The default is . The last element in the sequence that passes the test in the specified predicate function. is . is . The source sequence is empty, or no element in the sequence satisfies the condition in predicate (via the returned task).

Returns the last element of a sequence that satisfies a specified condition.

Returns the last element of a sequence, or a default value if the sequence contains no elements.

The type of the elements of source. An to return an element from. The to monitor for cancellation requests. The default is . The default value of if the source sequence is empty; otherwise, the last element in the . is .

Returns the last element of a sequence, or a default value if the sequence contains no elements.

The type of the elements of . An to return the last element of. The default value to return if the sequence is empty. The to monitor for cancellation requests. The default is . if the source sequence is empty; otherwise, the last element in the . is .

Returns the last element of a sequence that satisfies a condition or a default value if no such element is found.

The type of the elements of . An to return an element from. A function to test each element for a condition. The to monitor for cancellation requests. The default is . The default value of if the sequence is empty or if no elements pass the test in the predicate function; otherwise, the last element that passes the test in the predicate function. is . is .

Returns the last element of a sequence that satisfies a condition or a default value if no such element is found.

The type of the elements of . An to return an element from. A function to test each element for a condition. The default value to return if the sequence is empty. The to monitor for cancellation requests. The default is . if the sequence is empty or if no elements pass the test in the predicate function; otherwise, the last element that passes the test in the predicate function. is . is .

Returns the last element of a sequence that satisfies a condition or a default value if no such element is found.

The type of the elements of . An to return an element from. A function to test each element for a condition. The default value to return if the sequence is empty. The to monitor for cancellation requests. The default is . if the sequence is empty or if no elements pass the test in the predicate function; otherwise, the last element that passes the test in the predicate function. is . is .

Correlates the elements of two sequences based on matching keys.

The first sequence to join. The sequence to join to the first sequence. A function to extract the join key from each element of the first sequence. A function to extract the join key from each element of the second sequence. A function to create a result element from two matching elements. An to use to hash and compare keys. The type of the elements of the first sequence. The type of the elements of the second sequence. The type of the keys returned by the key selector functions. The type of the result elements. An that has elements of type that are obtained by performing a left outer join on two sequences. is . is . is . is . is .

Correlates the elements of two sequences based on matching keys.

The first sequence to join. The sequence to join to the first sequence. A function to extract the join key from each element of the first sequence. A function to extract the join key from each element of the second sequence. A function to create a result element from two matching elements. An to use to hash and compare keys. The type of the elements of the first sequence. The type of the elements of the second sequence. The type of the keys returned by the key selector functions. The type of the result elements. An that has elements of type that are obtained by performing a left outer join on two sequences. is . is . is . is . is .

Returns the maximum value in a generic sequence.

The type of the elements of . A sequence of values to determine the maximum value of. The to compare values. The to monitor for cancellation requests. The default is . The maximum value in the sequence. is . No object in implements the or interface (via the returned task). If type implements , the method uses that implementation to compare values. Otherwise, if type implements , that implementation is used to compare values. If is a reference type and the source sequence is empty or contains only values that are , this method returns .

Returns the maximum value in a sequence of values.

A sequence of values to determine the maximum value of. The to monitor for cancellation requests. The default is . The maximum value in the sequence.

Returns the maximum value in a sequence of values.

A sequence of values to determine the maximum value of. The to monitor for cancellation requests. The default is . The maximum value in the sequence.

Returns the maximum value in a sequence of nullable values.

A sequence of nullable values to determine the maximum value of. The to monitor for cancellation requests. The default is . The maximum value in the sequence.

Returns the maximum value in a sequence of nullable values.

A sequence of nullable values to determine the maximum value of. The to monitor for cancellation requests. The default is . The maximum value in the sequence.

Returns the maximum value in a generic sequence according to a specified key selector function.

The type of the elements of . The type of key to compare elements by. A sequence of values to determine the maximum value of. A function to extract the key for each element. The to compare keys. The to monitor for cancellation requests. The default is . The value with the maximum key in the sequence. is . No key extracted from implements the or interface. If is a reference type and the source sequence is empty or contains only values that are , this method returns .

Returns the maximum value in a generic sequence according to a specified key selector function.

Returns the minimum value in a generic sequence.

The type of the elements of . A sequence of values to determine the minimum value of. The to compare values. The to monitor for cancellation requests. The default is . The minimum value in the sequence. is . No object in implements the or interface. If type implements , the method uses that implementation to compare values. Otherwise, if type implements , that implementation is used to compare values. If is a reference type and the source sequence is empty or contains only values that are , this method returns .

Returns the minimum value in a sequence of values.

A sequence of values to determine the minimum value of. The to monitor for cancellation requests. The default is . The minimum value in the sequence.

Returns the minimum value in a sequence of values.

A sequence of values to determine the minimum value of. The to monitor for cancellation requests. The default is . The minimum value in the sequence.

Returns the minimum value in a sequence of nullable values.

A sequence of nullable values to determine the minimum value of. The to monitor for cancellation requests. The default is . The minimum value in the sequence.

Returns the minimum value in a sequence of nullable values.

A sequence of nullable values to determine the minimum value of. The to monitor for cancellation requests. The default is . The minimum value in the sequence.

Returns the minimum value in a generic sequence according to a specified key selector function.

The type of the elements of . The type of key to compare elements by. A sequence of values to determine the minimum value of. A function to extract the key for each element. The to compare keys. The to monitor for cancellation requests. The default is . The value with the minimum key in the sequence. is . No key extracted from implements the or interface. If is a reference type and the source sequence is empty or contains only values that are , this method returns .

Returns the minimum value in a generic sequence according to a specified key selector function.

Filters the elements of a based on a specified type .

The type to filter the elements of the sequence on. The whose elements to filter. An that contains elements from the input sequence of type .

Sorts the elements of a sequence in ascending order.

The type of the elements of . A sequence of values to order. An to compare keys. An whose elements are sorted. is .

Sorts the elements of a sequence in ascending order.

The type of the elements of . The type of the key returned by . A sequence of values to order. A function to extract a key from an element. An to compare keys. An whose elements are sorted according to a key. is . is .

Sorts the elements of a sequence in ascending order.

Sorts the elements of a sequence in descending order.

The type of the elements of . A sequence of values to order. An to compare keys. An whose elements are sorted in descending order. is .

Sorts the elements of a sequence in descending order.

Performs a subsequent ordering of the elements in a sequence in ascending order.

The type of the elements of . The type of the key returned by . A sequence of values to order. A function to extract a key from each element. An to compare keys. An whose elements are sorted according to a key. is . is .

Performs a subsequent ordering of the elements in a sequence in ascending order.

Performs a subsequent ordering of the elements in a sequence in descending order.

Function that returns its input unmodified.

Used for reference equality in order to avoid unnecessary computation when a caller can benefit from knowing that the produced value is identical to the input.

Adds a value to the beginning of the sequence.

The type of the elements of source. A sequence of values. The value to prepend to source. A new sequence that begins with element. is .

Generates a sequence of integral numbers within a specified range.

The value of the first integer in the sequence. The number of sequential integers to generate. An that contains a range of sequential integral numbers. is less than 0 + -1 is larger than .

Generates a sequence that contains one repeated value.

The type of the value to be repeated in the result sequence. The value to be repeated. The number of times to repeat the value in the generated sequence. An that contains a repeated value. is less than 0.

Inverts the order of the elements in a sequence.

The type of the elements of source. A sequence of values to reverse. A sequence whose elements correspond to those of the input sequence in reverse order. is .

Correlates the elements of two sequences based on matching keys.

The first sequence to join. The sequence to join to the first sequence. A function to extract the join key from each element of the first sequence. A function to extract the join key from each element of the second sequence. A function to create a result element from two matching elements. An to use to hash and compare keys. The type of the elements of the first sequence. The type of the elements of the second sequence. The type of the keys returned by the key selector functions. The type of the result elements. An that has elements of type that are obtained by performing a right outer join on two sequences. is . is . is . is . is .

Correlates the elements of two sequences based on matching keys.

The first sequence to join. The sequence to join to the first sequence. A function to extract the join key from each element of the first sequence. A function to extract the join key from each element of the second sequence. A function to create a result element from two matching elements. An to use to hash and compare keys. The type of the elements of the first sequence. The type of the elements of the second sequence. The type of the keys returned by the key selector functions. The type of the result elements. An that has elements of type that are obtained by performing a right outer join on two sequences. is . is . is . is . is .

Projects each element of a sequence into a new form.

The type of the elements of source. The type of the value returned by selector. A sequence of values to invoke a transform function on. A transform function to apply to each element. An whose elements are the result of invoking the transform function on each element of source. is . is .

Projects each element of a sequence into a new form.

Projects each element of a sequence into a new form by incorporating the element's index.

The type of the elements of source. The type of the value returned by selector. A sequence of values to invoke a transform function on. A transform function to apply to each element; the second parameter of the function represents the index of the source element. An whose elements are the result of invoking the transform function on each element of source. is . is .

Projects each element of a sequence into a new form by incorporating the element's index.

Projects each element of a sequence to an and flattens the resulting sequences into one sequence.

The type of the elements of source. The type of the elements of the sequence returned by selector. A sequence of values to project. A transform function to apply to each element. An whose elements are the result of invoking the one-to-many transform function on each element of the input sequence. is . is .

Projects each element of a sequence to an and flattens the resulting sequences into one sequence.

Projects each element of a sequence to an and flattens the resulting sequences into one sequence. The index of each source element is used in the projected form of that element.

Projects each element of a sequence to an , flattens the resulting sequences into one sequence, and invokes a result selector function on each element therein. The index of each source element is used in the intermediate projected form of that element.

The type of the elements of source. The type of the intermediate elements collected by . The type of the elements of the resulting sequence. A sequence of values to project. A transform function to apply to each element of the input sequence. A transform function to apply to each element of the intermediate sequence. An whose elements are the result of invoking the one-to-many transform function on each element of source and then mapping each of those sequence elements and their corresponding source element to a result element. is . is . is .

Projects each element of a sequence to an , flattens the resulting sequences into one sequence, and invokes a result selector function on each element therein.

Determines whether two sequences are equal by comparing their elements.

An to compare to . An to compare to the first sequence. An to use to compare elements. The to monitor for cancellation requests. The default is . if the two source sequences are of equal length and their corresponding elements compare equal according to comparer; otherwise, .

Shuffles the order of the elements of a sequence.

The type of the elements of . A sequence of values to shuffle. A sequence whose elements correspond to those of the input sequence in randomized order. Randomization is performed using a non-cryptographically secure random number generator.

Returns the only element of a sequence, and throws an exception if there is not exactly one element in the sequence.

The type of the elements of source. An to return the single element of. The to monitor for cancellation requests. The default is . The single element of the input sequence. is . The sequence is empty (via the returned task). The sequence contains more than one element. (via the returned task).

Returns the only element of a sequence that satisfies a specified condition, and throws an exception if more than one such element exists.

The type of the elements of source. An to return the single element of. A function to test an element for a condition. The to monitor for cancellation requests. The default is . The single element of the input sequence that satisfies a condition. is . is . The sequence is empty (via the returned task). No element satisfies the condition in (via the returned task). More than one element satisfies the condition in (via the returned task).

Returns the only element of a sequence that satisfies a specified condition, and throws an exception if more than one such element exists.

Returns the only element of a sequence, or a default value if the sequence is empty; this method throws an exception if there is more than one element in the sequence.

The type of the elements of source. An to return the single element of. The to monitor for cancellation requests. The default is . The single element of the input sequence, or the default value of if the sequence contains no elements. is . The sequence contains more than one element. (via the returned task).

Returns the only element of a sequence, or a default value if the sequence is empty; this method throws an exception if there is more than one element in the sequence.

The type of the elements of . An to return the single element of. The default value to return if the sequence is empty. The to monitor for cancellation requests. The default is . The single element of the input sequence, or if the sequence contains no elements. is . The input sequence contains more than one element.

Returns the only element of a sequence that satisfies a specified condition or a default value if no such element exists; this method throws an exception if more than one element satisfies the condition.

The type of the elements of . An to return the single element of. A function to test an element for a condition. The to monitor for cancellation requests. The default is . The single element of the input sequence that satisfies the condition, or the default value of if no such element is found. is . is . The input sequence contains more than one element.

The type of the elements of . An to return a single element from. A function to test an element for a condition. The default value to return if the sequence is empty. The to monitor for cancellation requests. The default is . The single element of the input sequence that satisfies the condition, or if no such element is found. is . is . More than one element satisfies the condition in .

Bypasses a specified number of elements in a sequence and then returns the remaining elements.

The type of the elements of source. An to return elements from. The number of elements to skip before returning the remaining elements. An that contains the elements that occur after the specified index in the input sequence. is .

Returns a new sequence that contains the elements from with the last elements of the source collection omitted.

The type of the elements of . An to return elements from. The number of elements to omit from the end of the sequence. A new sequence that contains the elements from minus elements from the end of the sequence. is .

Bypasses elements in a sequence as long as a specified condition is true and then returns the remaining elements.

The type of the elements of source. An to return elements from. A function to test each element for a condition. An that contains the elements from the input sequence starting at the first element in the linear series that does not pass the test specified by predicate. is . is .

Bypasses elements in a sequence as long as a specified condition is true and then returns the remaining elements.

Bypasses elements in a sequence as long as a specified condition is true and then returns the remaining elements. The element's index is used in the logic of the predicate function.

The type of the elements of source. An to return elements from. A function to test each element for a condition; the second parameter of the function represents the index of the source element. An that contains the elements from the input sequence starting at the first element in the linear series that does not pass the test specified by predicate. is . is .

Bypasses elements in a sequence as long as a specified condition is true and then returns the remaining elements. The element's index is used in the logic of the predicate function.

Computes the sum of a sequence of values.

A sequence of values to calculate the sum of. The to monitor for cancellation requests. The default is . The sum of the values in the sequence. is . The sum is larger than .

Computes the sum of a sequence of values.

A sequence of values to calculate the sum of. The to monitor for cancellation requests. The default is . The sum of the values in the sequence. is . The sum is larger than .

Computes the sum of a sequence of values.

A sequence of values to calculate the sum of. The to monitor for cancellation requests. The default is . The sum of the values in the sequence. is .

Computes the sum of a sequence of values.

A sequence of values to calculate the sum of. The to monitor for cancellation requests. The default is . The sum of the values in the sequence. is .

Computes the sum of a sequence of values.

A sequence of values to calculate the sum of. The to monitor for cancellation requests. The default is . The sum of the values in the sequence. is .

Computes the sum of a sequence of nullable values.

A sequence of nullable values to calculate the sum of. The to monitor for cancellation requests. The default is . The sum of the values in the sequence. is . The sum is larger than .

Computes the sum of a sequence of nullable values.

A sequence of nullable values to calculate the sum of. The to monitor for cancellation requests. The default is . The sum of the values in the sequence. is . The sum is larger than .

Computes the sum of a sequence of nullable values.

A sequence of nullable values to calculate the sum of. The to monitor for cancellation requests. The default is . The sum of the values in the sequence. is .

Computes the sum of a sequence of nullable values.

A sequence of nullable values to calculate the sum of. The to monitor for cancellation requests. The default is . The sum of the values in the sequence. is .

Computes the sum of a sequence of nullable values.

A sequence of nullable values to calculate the sum of. The to monitor for cancellation requests. The default is . The sum of the values in the sequence. is .

Returns a specified number of contiguous elements from the start of a sequence.

The type of the elements of source. The sequence to return elements from. The number of elements to return. An that contains the specified number of elements from the start of the input sequence. is .

Returns a specified range of contiguous elements from a sequence.

The type of the elements of . The sequence to return elements from. The range of elements to return, which has start and end indexes either from the start or the end. An that contains the specified of elements from the sequence. This method is implemented by using deferred execution. The immediate return value is an object that stores all the information that is required to perform the action. The query represented by this method is not executed until the object is enumerated either by calling its `GetEnumerator` method directly or by using `foreach` in Visual C# or `For Each` in Visual Basic. Take enumerates and yields elements whose indices belong to the specified . is .

Returns a new sequence that contains the last elements from .

The type of the elements in . A sequence to return elements from. The number of elements to take from the end of the sequence. A new sequence that contains the last elements from .

Returns elements from a sequence as long as a specified condition is true.

The type of the elements of source. A sequence to return elements from. A function to test each element for a condition. An that contains the elements from the input sequence that occur before the element at which the test no longer passes. is . is .

Returns elements from a sequence as long as a specified condition is true.

Returns elements from a sequence as long as a specified condition is true. The element's index is used in the logic of the predicate function.

Creates an array from an .

The type of the elements of source. An to create an array from. The to monitor for cancellation requests. The default is . An array that contains the elements from the input sequence. is .

Creates a new that iterates through .

The type of the elements of source. An of the elements to enumerate. An containing the sequence of elements from . is . Each iteration through the resulting will iterate through the .

Creates a from an according to specified key comparer.

The type of the keys from elements of The type of the values from elements of The to create a from. An to compare keys. The to monitor for cancellation requests. The default is . A that contains keys and values from . is . contains one or more duplicate keys (via the returned task).

Creates a from an according to specified key comparer.

Creates a from an according to a specified key selector function.

The type of the elements of source. The type of the keys returned by . An to create a from. A function to extract a key from each element. An to compare keys. The to monitor for cancellation requests. The default is . A that contains keys and values. is . is . contains one or more duplicate keys (via the returned task).

Creates a from an according to a specified key selector function.

Creates a from an "/> according to specified key selector and element selector functions.

The type of the elements of source. The type of the key returned by . The type of the value returned by . An to create a from. A function to extract a key from each element. A transform function to produce a result element value from each element. An to compare keys. The to monitor for cancellation requests. The default is . A that contains values of type selected from the input sequence. is . is . is . contains one or more duplicate keys (via the returned task).

Creates a from an "/> according to specified key selector and element selector functions.

Creates a from an .

The type of the elements of . An to create a from. An to compare keys. The to monitor for cancellation requests. The default is . A that contains values of type selected from the input sequence. is .

Creates a list from an .

The type of the elements of source. An to create a list from. The to monitor for cancellation requests. The default is . A list that contains the elements from the input sequence. is .

Creates a from an according to a specified key selector function.

The type of the elements of . The type of the key returned by . The to create a from. A function to extract a key from each element. An to compare keys. The to monitor for cancellation requests. The default is . A that contains keys and values. is . is .

Creates a from an according to a specified key selector function.

Creates a from an according to a specified key selector function and element selector functions.

The type of the elements of . The type of the key returned by . The type of the value returned by . The to create a from. A function to extract a key from each element. A transform function to produce a result element value from each element. An to compare keys. The to monitor for cancellation requests. The default is . A that contains keys and values. is . is .

Creates a from an according to a specified key selector function and element selector functions.

Produces the set union of two sequences.

An whose distinct elements form the first set for the union. An whose distinct elements form the second set for the union. An to compare keys. An that contains the elements from both input sequences, excluding duplicates. is . is .

Produces the set union of two sequences according to a specified key selector function.

The type of the elements of the input sequences. The type of key to identify elements by. An whose distinct elements form the first set for the union. An whose distinct elements form the second set for the union. A function to extract the key for each element. The to compare values. An that contains the elements from both input sequences, excluding duplicates. is . is .

Produces the set union of two sequences according to a specified key selector function.

Filters a sequence of values based on a predicate.

The type of the elements of . An to filter. A function to test each element for a condition. An that contains elements from the input sequence that satisfy the condition. is . is .

Filters a sequence of values based on a predicate.

The type of the elements of . An to filter. A function to test each element for a condition. An that contains elements from the input sequence that satisfy the condition. is . is .

Filters a sequence of values based on a predicate. Each element's index is used in the logic of the predicate function.

The type of the elements of . An to filter. A function to test each element for a condition; the second parameter of the function represents the index of the source element. An that contains elements from the input sequence that satisfy the condition. is . is .

Filters a sequence of values based on a predicate. Each element's index is used in the logic of the predicate function.

Applies a specified function to the corresponding elements of two sequences, producing a sequence of the results.

The type of the elements of the first input sequence. The type of the elements of the second input sequence. The type of the elements of the result sequence. The first sequence to merge. The second sequence to merge. A function that specifies how to merge the elements from the two sequences. An that contains merged elements of two input sequences. is . is . is .

Applies a specified function to the corresponding elements of two sequences, producing a sequence of the results.

Produces a sequence of tuples with elements from the two specified sequences.

The type of the elements of the first input sequence. The type of the elements of the second input sequence. The first sequence to merge. The second sequence to merge. A sequence of tuples with elements taken from the first and second sequences, in that order. is . is .

Produces a sequence of tuples with elements from the three specified sequences.

The type of the elements of the first input sequence. The type of the elements of the second input sequence. The type of the elements of the third input sequence. The first sequence to merge. The second sequence to merge. The third sequence to merge. A sequence of tuples with elements taken from the first, second, and third sequences, in that order. is . is . is .

Represents a sorted asynchronous sequence.

The type of the elements of the sequence. This interface is not intended to be implemented by user code. It supports the .NET infrastructure.

Performs a subsequent ordering on the elements of an according to a key.

The type of the key produced by . The function used to extract the key for each element. The used to compare keys for placement in the returned sequence. true to sort the elements in descending order; false to sort the elements in ascending order. An whose elements are sorted according to a key.

Performs a subsequent ordering on the elements of an according to a key.

An immutable node in a singly-linked list of items.

The type of the node's item.

Constructs a tail node.

The item to place in the tail node.

Constructs a node linked to the specified node.

The linked node. The item to place in this node.

The item held by this node.

The next node in the singly-linked list.

Creates a new node that holds the specified item and is linked to this node.

The item to place in the new node.

Gets the number of items in this and subsequent nodes by walking the linked list.

Gets the node at a logical index by walking the linked list.

The logical index. The caller should make sure is less than this node's count.

Returns an array that contains the items of this node's singly-linked list in reverse.

The number of items in this node.

Fills a start of a span with the items of this node's singly-linked list.

The span to fill. Must be at least the size required.

Fills the end of a span with the items of this node's singly-linked list in reverse.

The span to fill.

Specifies the priority of a member in overload resolution. When unspecified, the default priority is 0.

Initializes a new instance of the class.

The priority of the attributed member. Higher numbers are prioritized, lower numbers are deprioritized. 0 is the default if no attribute is present.

The priority of the member.

Attribute used to indicate a source generator should create a function for marshalling arguments instead of relying on the runtime to generate an equivalent marshalling function at run-time.

This attribute is meaningless if the source generator associated with it is not enabled. The current built-in source generator only supports C# and only supplies an implementation when applied to static, partial, non-generic methods.

Initializes a new instance of the .

Name of the library containing the import.

Gets the name of the library containing the import.

Gets or sets the name of the entry point to be called.

Gets or sets how to marshal string arguments to the method.

If this field is set to a value other than , must not be specified.

Gets or sets the used to control how string arguments to the method are marshalled.

If this field is specified, must not be specified or must be set to .

Gets or sets whether the callee sets an error (SetLastError on Windows or errno on other platforms) before returning from the attributed method.

Specifies how strings should be marshalled for generated p/invokes

Indicates the user is supplying a specific marshaller in .

Use the platform-provided UTF-8 marshaller.

Use the platform-provided UTF-16 marshaller.

Enumeration yielded no results

Sequence contains more than one element

Sequence contains more than one matching element

Sequence contains no elements

Sequence contains no matching element

Specifies that null is allowed as an input even if the corresponding type disallows it.

Specifies that null is disallowed as an input even if the corresponding type allows it.

Specifies that an output may be null even if the corresponding type disallows it.

Specifies that an output will not be null even if the corresponding type allows it. Specifies that an input argument was not null when the call returns.

Specifies that when a method returns , the parameter may be null even if the corresponding type disallows it.

Initializes the attribute with the specified return value condition.

The return value condition. If the method returns this value, the associated parameter may be null.

Gets the return value condition.

Specifies that when a method returns , the parameter will not be null even if the corresponding type allows it.

Initializes the attribute with the specified return value condition.

The return value condition. If the method returns this value, the associated parameter will not be null.

Gets the return value condition.

Specifies that the output will be non-null if the named parameter is non-null.

Initializes the attribute with the associated parameter name.

The associated parameter name. The output will be non-null if the argument to the parameter specified is non-null.

Gets the associated parameter name.

Applied to a method that will never return under any circumstance.

Specifies that the method will not return if the associated Boolean parameter is passed the specified value.

Initializes the attribute with the specified parameter value.

The condition parameter value. Code after the method will be considered unreachable by diagnostics if the argument to the associated parameter matches this value.

Gets the condition parameter value.

Specifies that the method or property will ensure that the listed field and property members have not-null values.

Initializes the attribute with a field or property member.

The field or property member that is promised to be not-null.

Initializes the attribute with the list of field and property members.

The list of field and property members that are promised to be not-null.

Gets field or property member names.

Specifies that the method or property will ensure that the listed field and property members have not-null values when returning with the specified return value condition.

Initializes the attribute with the specified return value condition and a field or property member.

The return value condition. If the method returns this value, the associated field or property member will not be null. The field or property member that is promised to be not-null.

Initializes the attribute with the specified return value condition and list of field and property members.

The return value condition. If the method returns this value, the associated field and property members will not be null. The list of field and property members that are promised to be not-null.

Gets the return value condition.

Gets field or property member names.

Provides downlevel polyfills for static methods on Exception-derived types.