| Name | Status | History |
|---|---|---|
| GitHub Actions |  |
LINQ to Objects is missing a few desirable features.
This project enhances LINQ to Objects with extra methods, in a manner which keeps to the spirit of LINQ.
Methods are provided to extend both IEnumerable<T> (via SuperLinq package)
and IAsyncEnumerable<T> (via SuperLinq.Async package).
SuperLinq is available for download and installation as a
NuGet package.
The documentation for the SuperLinq methods can be found here.
SuperLinq.Async is available for download and installation as a
NuGet package.
The documentation for the SuperLinq.Async methods can be found here.
Sorting Data
A sorting operation orders the elements of a sequence based on one or more attributes. The first sort criterion performs a primary sort on the elements. By specifying a second sort criterion, you can sort the elements within each primary sort group.
| Method Name | Description | Sync doc | Async doc |
|---|---|---|---|
| OrderBy | Sorts the elements of a sequence in a particular direction (ascending, descending) according to a key | link | link |
| ThenBy | Performs a subsequent ordering of elements in a sequence in a particular direction (ascending, descending) according to a key | link | link |
| PartialSort | Executes a partial sort of the top N elements of a sequence. If N is less than the total number of elements in the sequence, then this method will improve performance. |
link | link |
| PartialSortBy | Executes a partial sort of the top N elements of a sequence according to a key. If N is less than the total number of elements in the sequence, then this method will improve performance. |
link | link |
| DensePartialSort | Executes a partial sort of the top N elements of a sequence, including ties. If N is less than the total number of elements in the sequence, then this method will improve performance. |
link | link |
| DensePartialSortBy | Executes a partial sort of the top N elements of a sequence, including ties according to a key. If N is less than the total number of elements in the sequence, then this method will improve performance. |
link | link |
| Shuffle | Sorts the elements of a sequence in a random order. | link | ⏱(#20) |
| RandomSubset | Sorts a given number of elements of a sequence in a random order. | link | ⏱(#20) |
Set Operations
Set operations in LINQ refer to query operations that produce a result set that is based on the presence or absence of equivalent elements within the same or separate collections (or sets).
| Method Name | Description | Sync doc | Async doc |
|---|---|---|---|
| DistinctBy | Removes duplicate values from a collection. | link | link |
| Duplicates | Returns the sequence of elements that are in the source sequence more than once. | link | link |
| ExceptBy | Returns the set difference, which means the elements of one collection that do not appear in a second collection. | link | link |
Filtering Data
Filtering refers to the operation of restricting the result set to contain only those elements that satisfy a specified condition. It is also known as selection.
| Method Name | Description | Sync doc | Async doc |
|---|---|---|---|
| Choose | Filters a sequence based on a projection method that returns a tuple containing bool value and a new projected value. |
link | link |
| Where | Filters a sequence of values based on an enumeration of boolean values. | link | link |
| WhereLead | Filters a sequence of values based on a predicate evaluated on the current value and a leading value. | link | link |
| WhereLag | Filters a sequence of values based on a predicate evaluated on the current value and a lagging value. | link | link |
Quantifier Operations
Quantifier operations return a boolean value that indicates whether the sequence length matches some criteria.
| Method Name | Description | Sync doc | Async doc |
|---|---|---|---|
| AtLeast | Determines whether or not the number of elements in the sequence is greater than or equal to the given integer. | link | link |
| AtMost | Determines whether or not the number of elements in the sequence is lesser than or equal to the given integer. | link | link |
| CountBetween | Determines whether or not the number of elements in the sequence is between an inclusive range of minimum and maximum integers. | link | link |
| Exactly | Determines whether or not the number of elements in the sequence is equals to the given integer. | link | link |
| TrySingle | Determines the cardinality of the sequence in the set { 0, 1, >1 }. |
link | link |
| HasDuplicates | Determines whether the sequence contains duplicates | link | link |
Projection Operations
Projection refers to the operation of transforming an object into a new form that may contain related information.
| Method Name | Description | Sync doc | Async doc |
|---|---|---|---|
| EquiZip | Joins the corresponding elements of up to four sequences producing a sequence of tuples containing them, asserting that all sequences have exactly the same length. | link | link |
| ZipLongest | Joins the corresponding elements of up to four sequences producing a sequence of tuples containing them, using default values for sequences that are shorter than the longest sequence. |
link | link |
| ZipShortest | Joins the corresponding elements of up to four sequences producing a sequence of tuples containing them, which has the same length as the shortest sequence. | link | link |
| CountDown | Provides a countdown counter for a given count of elements at the tail of the sequence. | link | link |
| TagFirstLast | Provides bool values indicating for each element whether it is the first or last element of the sequence. |
link | link |
| Index | Provides an int value indicating the current index of each element of the sequence. |
link | link |
| IndexBy | Provides an int value indicating the current index of each element of the sequence within a group of items defined by a common attribute. |
link | link |
| Lag | Joins each element of the sequence with n-th previous element of the same sequence. | link | link |
| Lead | Joins each element of the sequence with n-th next element of the same sequence. | link | link |
| Rank | Provides an int value indicating the current rank of each element of the sequence. |
link | link |
| RankBy | Provides an int value indicating the current rank of each element of the sequence according to a key. |
link | link |
| DenseRank | Provides an int value indicating the current rank of each element of the sequence, counting ties as a single element. |
link | link |
| DenseRankBy | Provides an int value indicating the current rank of each element of the sequence according to a key, counting ties as a single element. |
link | link |
| Evaluate | Transforms a sequence of functions to a sequence of values returned by the functions. | link | N/A1 |
| ZipMap | Applies a function to each element in a sequence and returns a sequence of tuples containing both the original item as well as the function result. | link | link |
Partitioning Data
Partitioning in LINQ refers to the operation of dividing an input sequence into one or more sections.
| Method Name | Description | Sync doc | Async doc |
|---|---|---|---|
| TakeEvery | Takes every n-th element of the sequence. | link | link |
| Take | Takes elements from a specified range of the sequence. | link | link |
| Exclude | Excludes elements from a specified range of the sequence. | link | ⏱(#10) |
| Move | Moves elements from a specified range of the sequence to a new index in the sequence. | link | ⏱(#27) |
| SkipUntil | Skips elements based on a predicate function until an element satisfies the condition, skipping this element as well. | link | link |
| TakeUntil | Takes elements based on a predicate function until an element satisfies the condition, taking this element as well. | link | link |
| Batch | Splits the elements of a sequence into chunks of a specified maximum size. | link | link |
| Buffer | Splits the elements of a sequence into chunks of a specified maximum size, where the chunks may be overlapping or have gaps. | link | link |
| Partition | Splits the elements of a sequence based on a common attribute and known key values. | link | link |
| Segment | Splits the elements of a sequence based on a condition function. | link | link |
| Split | Splits the elements of a sequence based on a separator value that is not returned. | link | link |
| Window | Returns a sequence of sequential windows of size N over the sequence. |
link | link |
| WindowLeft | Returns a sequence of sequential windows of up to size N over the sequence. |
link | link |
| WindowRight | Returns a sequence of sequential windows of up to size N over the sequence. |
link | link |
Join Operations
A join of two data sources is the association of objects in one data source with objects that share a common attribute in another data source.
| Method Name | Description | Sync doc | Async doc |
|---|---|---|---|
| Cartesian | Executes a cartesian product (join without any key) of up to eight sequences. | link | N/A1 |
| FullGroupJoin | Joins two sequences based on key selector functions, returning two lists containing the values on each side that match according to the key. | link | N/A1 |
| FullOuterJoin | Joins two sequences based on key selector functions, returning default values if either sequence does not have a matching key. |
link | link |
| InnerJoin | Joins two sequences based on key selector functions. | link | link |
| LeftOuterJoin | Joins two sequences based on key selector functions, returning default values if the second sequence does not have a matching key. |
link | link |
| RightOuterJoin | Joins two sequences based on key selector functions, returning default values if the first sequence does not have a matching key. |
link | link |
Grouping Data
Grouping refers to the operation of putting data into groups so that the elements in each group share a common attribute.
| Method Name | Description | Sync doc | Async doc |
|---|---|---|---|
| DistinctUntilChanged | Takes the first element of each adjacent group of elements that share a common attribute. | link | link |
| GroupAdjacent | Groups adjacent elements that share a common attribute. | link | link |
| RunLengthEncode | Takes the first element of each adjacent group of equivalent elements along with the number of elements in the group. | link | link |
Generation Operations
Generation refers to creating a new sequence of values.
| Method Name | Description | Sync doc | Async doc |
|---|---|---|---|
| Generate | Generates a sequence based on a seed value and subsequent executions of a generator function. | link | link |
| From | Generates a sequence from the results of executing one or more provided functions. | link | link |
| Return | Generates a single-element sequence containing the provided value. | link | link |
| Sequence | Generates a sequence of numbers between a starting and ending value. | link | link |
| Range | Generates a sequence of numbers. | link | link |
| Random | Generates a sequence of random int values. |
link | link |
| RandomDouble | Generates a sequence of random double values. |
link | link |
| Repeat | Generates a sequence that infinitely repeats the input sequence. | link | link |
| DoWhile | Generates a sequence that repeats the input sequence at least once, as long as a given condition is true. |
link | link |
| While | Generates a sequence that repeats the input sequence as long as a given condition is true. |
link | link |
| Retry | Generates a sequence that repeats the input sequence as long as the input sequence encounters an error. | link | link |
| Throw | Generates a sequence that throws an exception upon enumeration. | link | link |
| Permutations | Generates a sequence of every possible permutation of the input sequence. | link | ⏱(#20) |
| Subsets | Generates a sequence of every possible subset of a given size of the input sequence. | link | ⏱(#20) |
| BindByIndex | Generates a sequence from another sequence by selecting elements at given indices. | link | link |
| ToArrayByIndex | Generates a sequence based on an index selector function applied to each element. | link | link |
| FallbackIfEmpty | Replaces an empty sequence with a default sequence. | link | link |
| FillBackward | Generates a sequence where missing values are replaced with the next good value. | link | link |
| FillForward | Generates a sequence where missing values are replaced with the last good value. | link | link |
| Pad | Generates a sequence with a minimum length, providing default values for missing elements. | link | link |
| PadStart | Generates a sequence with a minimum length, providing default values for missing elements. | link | link |
Selection Operations
Selection operations choose which sequence to based on a criteria evaluated at the time of enumeration.
| Method Name | Description | Sync doc | Async doc |
|---|---|---|---|
| Amb | Enumerates the first sequence to return the first value. | N/A2 | link |
| Case | Enumerates a sequence chosen by a function executed at the time of enumeration. | link | link |
| If | Enumerates a sequence chosen by a condition function executed at the time of enumeration. | link | link |
| Defer | Enumerates a sequence returned by a function executed at the time of enumeration. | link | link |
| Using | Creates a disposable resource at the time of execution and enumerates a sequence based on the resource. | link | link |
Equality Operations
Equality operations return a boolean value that indicates whether two sequences match according to some criteria.
| Method Name | Description | Sync doc | Async doc |
|---|---|---|---|
| CollectionEqual | Determines whether two sequences contain the same elements in any order. | link | link |
| CompareCount | Determines whether two sequences have the same length. | link | link |
| StartsWith | Determines whether a sequence contains another sequence at the start. | link | link |
| EndsWith | Determines whether a sequence contains another sequence at the end. | link | link |
Element Operations
Element operations return or find the index of a single, specific element from a sequence.
| Method Name | Description | Sync doc | Async doc |
|---|---|---|---|
| ElementAt | Returns the element at a specified index in a collection. | link | link |
| ElementAtOrDefault | Returns the element at a specified index in a collection or a default value if the index is out of range. | link | link |
| FindIndex | Returns the index of the first element that satisfies a given criteria. | link | link |
| FindLastIndex | Returns the index of the last element that satisfies a given criteria. | link | link |
| IndexOf | Returns the first index of the element. | link | link |
| LastIndexOf | Returns the last index of the element. | link | link |
Converting Data Types
Element operations return or find a single, specific element from a sequence.
| Method Name | Description | Sync doc | Async doc |
|---|---|---|---|
| CopyTo | Copies the elements from a sequence into a provided list-like structure. | link | link |
| ToDataTable | Converts a sequence of objects into a DataTable object. |
link | N/A3 |
| ToDelimitedString | Converts a sequence of elements to a delimited string containing the string form of each element. |
link | N/A1 |
| ToDictionary | Converts a sequence of KeyValuePair or (key, value) tuples into a Dictionary<,> |
link | N/A1 |
| ToLookup | Converts a sequence of KeyValuePair or (key, value) tuples into a Lookup<,> |
link | N/A1 |
| Transpose | Transposes a jagged two-dimensional array of elements, such that, for example, each row of the returned 2d array contains the first element of each inner array of the input. | link | N/A1 |
Concatenation Operations
Concatenation refers to the operation of appending one sequence to another.
| Method Name | Description | Sync doc | Async doc |
|---|---|---|---|
| ConcurrentMerge | Merges the elements of two or more asynchronous sequences into a single sequence. | N/A2 | link |
| Flatten | Flattens a sequence containing arbitrarily-nested sequences into a single sequence. | link | N/A4 |
| Insert | Inserts the elements of a sequence into another sequence at a specified index. | link | link |
| Interleave | Interleaves the elements of two or more sequences into a single sequence. | link | link |
| Replace | Replaces a range of elements in a sequence with the elements from another sequence. | link | link |
| Catch | Concatenates one or more sequences until one is completely enumerated without error. | link | link |
| OnErrorResumeNext | Concatenates one or more sequences regardless of if an error occurs in any of them. | link | link |
| SortedMerge | Merges already-sorted sequences into a new correctly-sorted sequence. | link | link |
| SortedMergeBy | Merges already-sorted sequences into a new correctly-sorted sequence according to a key value. | link | link |
Aggregation Operations
An aggregation operation computes a single value from a collection of values.
| Method Name | Description | Sync doc | Async doc |
|---|---|---|---|
| Aggregate | Performs two or more custom aggregation operation on the values of a sequence. | link | link |
| AggregateBy | Groups elements that share a common attribute and returns a sequence of attributes along with the accumlated value for each group. | link | link |
| AggregateRight | Performs a custom aggregation on a sequence, starting from the end. | link | link |
| Scan | Performs a custom aggregation on a sequence, returning the intermediate aggregate value for each element in the sequence. | link | link |
| PreScan | Performs a custom aggregation on a sequence, returning the pre-intermediate aggregate value for each element in the sequence. | link | link |
| ScanBy | Performs a custom aggregation on each group of elements that share a common attribute, returning the intermediate aggregate value for each element in the sequence. | link | link |
| ScanRight | Performs a custom aggregation on a sequence, returning the intermediate aggregate value for each element in the sequence, starting from the end of the sequence. | link | link |
| CountBy | Groups elements that share a common attribute and returns a sequence of attributes along with the number of elements in each group. | link | link |
| Fold | Collects the elements of an up to 16 element sequence and projects them into a single value. | link | link |
| MaxItems | Determines the list of maximum values in a collection. | link | link |
| MaxItemsBy | Determines the list of maximum values in a collection. | link | link |
| MinItems | Determines the list of minimum values in a collection. | link | link |
| MinItemsBy | Determines the list of minimum values in a collection. | link | link |
Buffering Operations
Buffering operations allow storing and sharing data from a sequence to be used in a source-friendly wawy.
| Method Name | Description | Sync doc | Async doc |
|---|---|---|---|
| Memoize | Lazily cache the elements of a sequence to be used in multiple re-iterations. | link | link |
| Publish | Share a sequence among multiple consumers, such that each consumer can receive every element returned by the source since the consumer began enumerating. | link | link |
| Share | Share a sequence among multiple consumers, such that each element returned by the source is only obtained by a single consumer. | link | link |
Sequence Operations
Sequence operations perform some operation on a sequence as a whole.
| Method Name | Description | Sync doc | Async doc |
|---|---|---|---|
| Consume | Immediately consumes and discards a sequence, allowing a lazy sequence that has side-effects to be completed. | link | link |
| ForEach | Immediately executes an action on every element in a sequence. | link | link |
| Do | Performs an action on each element in a sequence as it is enumerated. | link | link |
| Timeout | Throws an exception if the async processing of an element takes longer than a specified timeout. | N/A2 | link |
| AssertCount | Evalutes the length of a sequence as it is enumerated and validates that the length is the same as expected. | link | link |
| Finally | Executes an action when a sequence finishes enumerating, regardless of whether or not the sequence completed successfully. | link | link |
Tree Operations
Tree operations allow processing tree-like data structures in a data-agnostic form.
| Method Name | Description | Sync doc | Async doc |
|---|---|---|---|
| TraverseBreadthFirst | Returns every node in a tree-like virtual structure expressed by the input methods in a breadth-first manner. | link | link |
| TraverseDepthFirst | Returns every node in a tree-like virtual structure expressed by the input methods in a depth-first manner. | link | link |
| GetShortestPath | Determine the shortest path through a graph-like virtual structure using Dijkstra's algorithm or A*. | link | link |
| GetShortestPathCost | Determine the cost of shortest path through a graph-like virtual structure using Dijkstra's algorithm or A*. | link | link |
| GetShortestPaths | Determine the shortest cost to every node in a graph-like virtual structure using Dijkstra's algorithm. | link | link |
Footnotes
-
Not yet implemented; open a ticket if operator is desired ↩ ↩2 ↩3 ↩4 ↩5 ↩6 ↩7
-
DataTableis an no-longer relevant data structure, so this method is only kept for posterity and will not be migrated to a datatable. ↩ -
Will not be implemented, due to complex nature of flattening async sequences into a single sequence ↩