### Run bench-runner Quick Start

Source: https://github.com/composewell/streamly/blob/master/benchmark/README.md

Execute the bench-runner with essential package information. Replace `./bench-runner` with the cabal run command if not installed.

```bash
bin/bench-runner --package-version 0.0.0 --package-name streamly-benchmarks
```

--------------------------------

### Quick Start bench-runner

Source: https://github.com/composewell/streamly/blob/master/docs/Developer/Benchmarks.md

Run all benchmark suites quickly using the `--quick` flag. Replace `./bench-runner` with `cabal run bench-runner --project-file=cabal.project.report --` if not installed.

```bash
bin/bench-runner --package-version 0.0.0 --package-name streamly-benchmarks
./bench-runner --quick
```

--------------------------------

### Build and Compile Standalone Example

Source: https://github.com/composewell/streamly/blob/master/benchmark/README.md

First, build the benchmark suite to generate the GHC environment file. Then, compile a standalone example file with specific optimization flags.

```bash
$ cabal build # build and write ghc environment file
$ ghc -O2 -fspec-constr-recursive=16 -fmax-worker-args=16 example.hs
```

--------------------------------

### Install bench-runner with Nix

Source: https://github.com/composewell/streamly/blob/master/benchmark/README.md

Install the bench-runner executable within a Nix shell environment.

```bash
$ cd benchmark/bench-runner
$ nix-shell --run 'cabal install bench-runner --installdir=../../  --overwrite-policy=always'
$ cd ../..
$ ./bench-runner <bench-runner-args>
```

--------------------------------

### Start GHCi with streamly-core

Source: https://github.com/composewell/streamly/blob/master/docs/User/Tutorials/using-streamly.md

Starts the GHCi REPL and loads the streamly-core package. This command may take time on the first run due to package building.

```bash
$ cabal repl --build-depends streamly-core
...
pleasing, the first time around ...
GHCi, version 9.2.2: https://www.haskell.org/ghc/  :? for help
ghci>
```

--------------------------------

### Rooted Path Combination Example

Source: https://github.com/composewell/streamly/blob/master/docs/Developer/FileSystem.Path.Design.rst

Shows an example of combining rooted paths where the drive is fixed but the current directory can change, illustrating a scenario where a 'combine' operation might be used.

```text
C:\x </> C:y -> C:\x\y
C:   </> C:y -> C:y    -- C: equiv C:./
C:x  </> C:y -> C:x\y
```

--------------------------------

### Install bench-runner with Cabal

Source: https://github.com/composewell/streamly/blob/master/benchmark/README.md

Install the bench-runner executable locally using a specific project file and overwrite policy.

```bash
$ cabal install bench-runner --project-file=cabal.project.report --installdir=./  --overwrite-policy=always
$ ./bench-runner <bench-runner-args>
```

--------------------------------

### Start GHCi with a specific streamly-core version

Source: https://github.com/composewell/streamly/blob/master/docs/User/Tutorials/using-streamly.md

Starts the GHCi REPL and loads a specific version of the streamly-core package using a version constraint.

```bash
$ cabal repl --build-depends streamly-core==0.1.0
...
ghci>
```

--------------------------------

### Doctest Setup Snippet

Source: https://github.com/composewell/streamly/blob/master/docs/Developer/Tests.md

A Haddock $setup section defines a snippet that is executed before any other doctests. Ensure snippets are not enclosed in @ .. @ markup.

```haskell
-- $setup
-- >>> :m
-- >>> import Control.Monad.IO.Class (MonadIO(..))
-- >>> import Data.Function ((&))
```

--------------------------------

### Create a project directory

Source: https://github.com/composewell/streamly/blob/master/docs/User/Tutorials/using-streamly.md

Creates a new directory for a Streamly project example.

```bash
$ mkdir streamly-project
```

--------------------------------

### Example Usage: Counting Code Points

Source: https://github.com/composewell/streamly/blob/master/docs/Developer/utf8-decoder.md

Demonstrates how to call the `countCodePoints` function and interpret its return value to check for malformed strings or get the character count.

```c
if (countCodePoints(s, &count)) {
  printf("The string is malformed\n");
} else {
  printf("The string is %u characters long\n", count);
}

```

--------------------------------

### Start GHCi REPL for Project

Source: https://github.com/composewell/streamly/blob/master/docs/User/Tutorials/using-streamly.md

Launch the GHCi REPL within your project context to interactively run code and load project modules.

```bash
$ cabal repl
...
Ok, one module loaded.
ghci> main
1
2
3
ghci>
```

--------------------------------

### Run bench-runner without Installation

Source: https://github.com/composewell/streamly/blob/master/benchmark/README.md

Execute the bench-runner directly using cabal run without a prior installation.

```bash
$ cabal run bench-runner --project-file=cabal.project.report -- <bench-runner-args>
```

--------------------------------

### Type Variable Ordering Example

Source: https://github.com/composewell/streamly/blob/master/CONTRIBUTING.md

Demonstrates the recommended ordering of type variables in `forall` declarations and constraints for streams.

```Haskell
func :: forall m a. (MonadIO m, Storable a) => ...
```

--------------------------------

### bench-runner Help and Target Selection

Source: https://github.com/composewell/streamly/blob/master/docs/Developer/Benchmarks.md

Get help for `bench-runner` or list available benchmark suites using `--targets help`. Run specific suites like `serial_grp` or multiple suites by name.

```bash
$ ./bench-runner --help
$ ./bench-runner --targets help # Show available benchmark suites
$ ./bench-runner --targets serial_grp # Run all serial benchmark suites
$ ./bench-runner --targets "Prelude.Serial Data.Parser" # run selected suites
```

--------------------------------

### Scanl Step Implementation Example

Source: https://github.com/composewell/streamly/blob/master/docs/Developer/Data.Scanl.md

Illustrates a step function within a postscan implementation, handling initialization and subsequent processing. It shows how to transition between states based on the result of an initial or step action.

```haskell
    step _ (ScanInit st) = do
        res <- initial
        return
            $ case res of
                  Partial fs -> Skip $ ScanDo st fs
                  Done b -> Yield b ScanDone
    step gst (ScanDo st fs) = do
        res <- sstep st
        case res of
            Yield x s -> do
    ...
```

--------------------------------

### Split Root Operation Examples

Source: https://github.com/composewell/streamly/blob/master/docs/Developer/FileSystem.Path.Design.rst

Demonstrates the behavior of the 'splitRoot' operation on various Posix and Windows paths, separating the root component from the unrooted path.

```text
splitRoot :: Rooted -> (Rooted, Unrooted)
-- Posix
splitRoot "/" => ("/", ".")
splitRoot "/x" => ("/", "x")
-- Windows
splitRoot "/" => ("/", ".")
splitRoot "/x" => ("/", "x")
splitRoot "C:" => ("C:", ".")
splitRoot "C:/" => ("C:/", ".")
splitRoot "//server/share" => ("//server/share", ".")
```

--------------------------------

### Running Cabal Tests Directly

Source: https://github.com/composewell/streamly/blob/master/CONTRIBUTING.md

Example of how to run Cabal tests directly with specific optimization flags and test details.

```bash
$ cabal test --disable-optimization --flags -opt --test-show-details=streaming --test-option=--color streamly-tests
```

--------------------------------

### Compile Standalone Example with Diagnostics

Source: https://github.com/composewell/streamly/blob/master/benchmark/README.md

Add GHC OPTIONS_GHC pragmas to a standalone Haskell file for detailed diagnostics, including dumping simplification and enabling verbose fusion plugin output.

```haskell
{-# OPTIONS_GHC
  -ddump-simpl
  -ddump-to-file
  -dsuppress-all
  -Wmissed-specialisations
  -Wall-missed-specialisations
  -fplugin Fusion.Plugin
  -fplugin-opt=Fusion.Plugin:verbose=2
  -fplugin-opt=Fusion.Plugin:dump-core
#-}
```

--------------------------------

### Internal Module Hierarchy Example

Source: https://github.com/composewell/streamly/blob/master/docs/Developer/module-organization.md

Illustrates a common naming convention for organizing different types of arrays (unboxed, boxed, mutable) within an internal module hierarchy.

```text
Streamly.Internal.Data.Array -- Unboxed arrays
Streamly.Internal.Data.Array.Generic -- Boxed arrays
Streamly.Internal.Data.MutArray -- Unboxed mutable arrays
Streamly.Internal.Data.MutArray.Generic -- Boxed mutable arrays
```

--------------------------------

### StreamD Coding Style Example

Source: https://github.com/composewell/streamly/blob/master/CONTRIBUTING.md

Illustrates the conventions for naming variables and structuring code within the StreamD library, focusing on scope.

```Haskell
mapM f (Stream step1 state1) = Stream step state
    where

    step gst st = do
        r <- step1 (adaptState gst) st
        case r of 
            Yield x s -> f x >>= \a -> return $ Yield a s
            Skip s    -> return $ Skip s
            Stop      -> return Stop
```

--------------------------------

### Rooted and Unrooted Path Definitions

Source: https://github.com/composewell/streamly/blob/master/docs/Developer/FileSystem.Path.Design.rst

Provides examples of paths classified as 'Rooted' (having anchoring semantics) and 'Unrooted' (pure appendable path branches).

```text
Examples of Rooted: "/", "/x", "C:", "C:x", "C:/", "//x/y".
Examples of Unrooted: "x", "x/y", ".", "./x", "..", "../x".
```

--------------------------------

### Compare Benchmark Results with Baseline

Source: https://github.com/composewell/streamly/blob/master/benchmark/README.md

Checkout baseline commits, run benchmarks, and append new results for comparison. Use --no-measure to display existing results.

```bash
# Checkout baseline commit
$ ./bench-runner --quick

# Checkout commit with new changes
$ ./bench-runner --quick --append

# To add another result to comparisons just repeat the above command on
# desired commit

# To display the current results without running the benchmarks.
# See "Reporting without measuring" for more info.
$ ./bench-runner --no-measure
```

--------------------------------

### bench-runner Help and Target Selection

Source: https://github.com/composewell/streamly/blob/master/benchmark/README.md

Display help information or select specific benchmark suites and targets for execution. Supports filtering by prefix and running specific benchmarks.

```bash
$ ./bench-runner --help
$ ./bench-runner --quick # run all the benchmark suites
$ ./bench-runner --targets help # Show available benchmark suites
$ ./bench-runner --targets serial_grp # Run all serial benchmark suites
$ ./bench-runner --targets "Prelude.Serial Data.Parser" # run selected suites
$ ./bench-runner --no-measure # don't run benchmarks just show previous results

# Run all O(1) space complexity benchmarks in `Prelude.Serial` suite
$ ./bench-runner --targets Prelude.Serial --prefix Prelude.Serial/o-1-space

# Run a specific benchmark in `Prelude.Serial` suite
$ ./bench-runner --targets Prelude.Serial --prefix Prelude.Serial/o-1-space.generation.unfoldr
```

--------------------------------

### getSlice

Source: https://github.com/composewell/streamly/blob/master/core/docs/ApiChangelogs/0.2.2-0.3.0.txt

Gets a slice of a mutable array.

```APIDOC
## getSlice

### Description
Gets a slice of a mutable array.

### Method
forall a. Unbox a => Int -> Int -> MutArray a -> MutArray a

### Parameters
#### Path Parameters
- **offset** (Int) - Required - The starting offset of the slice.
- **length** (Int) - Required - The length of the slice.
- **array** (MutArray a) - Required - The mutable array to slice.

### Response
#### Success Response
- **MutArray a** - The resulting slice of the mutable array.

```

--------------------------------

### Build Benchmark Suite with Fusion Plugin

Source: https://github.com/composewell/streamly/blob/master/benchmark/README.md

Build a specific benchmark suite, 'bench:Prelude.Serial', with the fusion-plugin enabled after applying diagnostic GHC options.

```bash
$ cabal build bench:Prelude.Serial --flag fusion-plugin
```

--------------------------------

### getSliceUnsafe

Source: https://github.com/composewell/streamly/blob/master/core/docs/ApiChangelogs/0.2.2-0.3.0.txt

Unsafely gets a slice of a mutable array.

```APIDOC
## getSliceUnsafe

### Description
Unsafely gets a slice of a mutable array.

### Method
forall a. Unbox a => Int -> Int -> MutArray a -> MutArray a

### Parameters
#### Path Parameters
- **offset** (Int) - Required - The starting offset of the slice.
- **length** (Int) - Required - The length of the slice.
- **array** (MutArray a) - Required - The mutable array to slice.

### Response
#### Success Response
- **MutArray a** - The resulting slice of the mutable array.

```

--------------------------------

### unsafeGetIndexRev

Source: https://github.com/composewell/streamly/blob/master/core/docs/ApiChangelogs/0.2.2-0.3.0.txt

Retrieves an element from a MutArray by index, starting from the end.

```APIDOC
## unsafeGetIndexRev

### Description
Retrieves an element from a MutArray by index, starting from the end. Requires MonadIO and Unbox constraints.

### Method
N/A (Function Signature)

### Endpoint
N/A

### Parameters
#### Path Parameters
None

#### Query Parameters
None

#### Request Body
None

### Request Example
None

### Response
#### Success Response
- **a**: The element at the specified index from the end.

#### Response Example
None
```

--------------------------------

### getIndexUnsafe

Source: https://github.com/composewell/streamly/blob/master/core/docs/ApiChangelogs/0.2.2-0.3.0.txt

Unsafely gets an element at a specific index from a mutable array.

```APIDOC
## getIndexUnsafe

### Description
Unsafely gets an element at a specific index from a mutable array.

### Method
forall m a. (MonadIO m, Unbox a) => Int -> MutArray a -> m a

### Parameters
#### Path Parameters
- **index** (Int) - Required - The index of the element to retrieve.
- **array** (MutArray a) - Required - The mutable array to get the element from.

### Response
#### Success Response
- **m a** - A monadic action returning the element at the specified index.

```

--------------------------------

### Streamly.Data.MutArray.Generic.getIndexUnsafe

Source: https://github.com/composewell/streamly/blob/master/core/docs/ApiChangelogs/0.2.2-0.3.0.txt

Unsafely gets a value from a specific index in a mutable array.

```APIDOC
## Streamly.Data.MutArray.Generic.getIndexUnsafe

### Description
Unsafely gets a value from a specific index in a mutable array. This operation is monadic and does not perform bounds checking.

### Method
Monadic Operation

### Endpoint
N/A

### Parameters
#### Path Parameters
N/A

#### Query Parameters
N/A

#### Request Body
N/A

### Request Example
N/A

### Response
#### Success Response (200)
- **m a** (type) - A monadic action that returns the value at the specified index.

#### Response Example
N/A
```

--------------------------------

### Run Doctests using Cabal and Cabal-Docspec

Source: https://github.com/composewell/streamly/blob/master/docs/Developer/Tests.md

Build all code first, then use cabal-docspec to run and check doctests. Options include setting a timeout and checking properties.

```bash
$ cabal build all
$ cabal-docspec --timeout 60 --check-properties --property-variables xs
```

--------------------------------

### Streamly.Data.MutArray.Generic.unsafeGetIndex

Source: https://github.com/composewell/streamly/blob/master/core/docs/ApiChangelogs/0.2.2-0.3.0.txt

Unsafely gets a value from a specific index in a mutable array.

```APIDOC
## Streamly.Data.MutArray.Generic.unsafeGetIndex

### Description
Unsafely gets a value from a specific index in a mutable array. This operation is monadic and does not perform bounds checking.

### Method
Monadic Operation

### Endpoint
N/A

### Parameters
#### Path Parameters
N/A

#### Query Parameters
N/A

#### Request Body
N/A

### Request Example
N/A

### Response
#### Success Response (200)
- **m a** (type) - A monadic action that returns the value at the specified index.

#### Response Example
N/A
```

--------------------------------

### Get the name of a data type

Source: https://github.com/composewell/streamly/blob/master/core/docs/ApiChangelogs/0.1.0-0.2.0.txt

Retrieves the name of a data type.

```haskell
[dtName] :: DataType -> Name
```

--------------------------------

### Get the name of a data constructor

Source: https://github.com/composewell/streamly/blob/master/core/docs/ApiChangelogs/0.1.0-0.2.0.txt

Retrieves the name of a data constructor.

```haskell
[dcName] :: DataCon -> Name
```

--------------------------------

### Windows Path Composition Rules (RelFixedDrive)

Source: https://github.com/composewell/streamly/blob/master/docs/Developer/FileSystem.Path.Design.rst

Illustrates how paths with a fixed drive are composed. If both paths have the same drive, they are combined; otherwise, a runtime error occurs. 'C:' is treated as equivalent to 'C:./'.

```text
C:\x </> C:y -> C:\x\y
C:   </> C:y -> C:y    -- C: equiv C:./
C:x  </> C:y -> C:x\y

D:x  </> C:y -> error
\x   </> C:y -> error
x    </> C:y -> error
```

--------------------------------

### sliceOffLen

Source: https://github.com/composewell/streamly/blob/master/core/docs/ApiChangelogs/0.2.2-0.3.0.txt

Slices a MutArray to extract a portion of a specified length starting from a given offset.

```APIDOC
## sliceOffLen

### Description
Slices a MutArray to extract a portion of a specified length starting from a given offset. Requires Unbox constraint.

### Method
N/A (Function Signature)

### Endpoint
N/A

### Parameters
#### Path Parameters
None

#### Query Parameters
None

#### Request Body
None

### Request Example
None

### Response
#### Success Response
- **MutArray a**: The sliced portion of the MutArray.

#### Response Example
None
```

--------------------------------

### Streamly.Data.Fold.foldl1M'

Source: https://github.com/composewell/streamly/blob/master/core/docs/ApiChangelogs/0.2.2-0.3.0.txt

A monadic fold that reduces a stream to a single value, starting from the first element.

```APIDOC
## Streamly.Data.Fold.foldl1M'

### Description
A monadic fold that reduces a stream to a single value using a binary monadic function. It starts the reduction from the first element of the stream. Returns `Maybe a` to handle empty streams.

### Method
Monadic Fold

### Endpoint
N/A

### Parameters
#### Path Parameters
N/A

#### Query Parameters
N/A

#### Request Body
N/A

### Request Example
N/A

### Response
#### Success Response (200)
- **Fold m a (Maybe a)** (type) - A fold that reduces a stream to a `Maybe` value.

#### Response Example
N/A
```

--------------------------------

### Create and Upload Source Distribution

Source: https://github.com/composewell/streamly/blob/master/docs/Developer/MAINTAINING.md

Create a source distribution (sdist) and upload it to Hackage. It's recommended to use a clean workspace to avoid shipping unintended files.

```bash
cabal v2-sdist; cabal upload <tarpath>
```

--------------------------------

### Compile and Run a Basic Streamly Project

Source: https://github.com/composewell/streamly/blob/master/docs/User/Tutorials/using-streamly.md

After initializing the project, you can compile and run the default application.

```bash
$ cabal run
Hello, Haskell!
```

--------------------------------

### Streamly.Data.Fold.foldlM1'

Source: https://github.com/composewell/streamly/blob/master/core/docs/ApiChangelogs/0.2.2-0.3.0.txt

A monadic fold that reduces a stream to a single value, starting from the first element.

```APIDOC
## Streamly.Data.Fold.foldlM1'

### Description
A monadic fold that reduces a stream to a single value using a binary monadic function. It starts the reduction from the first element of the stream. Returns `Maybe a` to handle empty streams.

### Method
Monadic Fold

### Endpoint
N/A

### Parameters
#### Path Parameters
N/A

#### Query Parameters
N/A

#### Request Body
N/A

### Request Example
N/A

### Response
#### Success Response (200)
- **Fold m a (Maybe a)** (type) - A fold that reduces a stream to a `Maybe` value.

#### Response Example
N/A
```

--------------------------------

### Streamly.Data.MutArray.getIndexUnsafe

Source: https://github.com/composewell/streamly/blob/master/core/docs/ApiChangelogs/0.2.2-0.3.0.txt

Unsafely gets a value from a specific index in a mutable array, with Unbox constraint.

```APIDOC
## Streamly.Data.MutArray.getIndexUnsafe

### Description
Unsafely gets a value from a specific index in a mutable array. Requires the element type `a` to have an `Unbox` instance. This operation is monadic and does not perform bounds checking.

### Method
Monadic Operation

### Endpoint
N/A

### Parameters
#### Path Parameters
N/A

#### Query Parameters
N/A

#### Request Body
N/A

### Request Example
N/A

### Response
#### Success Response (200)
- **m a** (type) - A monadic action that returns the value at the specified index.

#### Response Example
N/A
```

--------------------------------

### Compare Benchmark Suites

Source: https://github.com/composewell/streamly/blob/master/docs/Developer/Benchmarks.md

Run comparison group benchmarks (ending in `_cmp`) to compare all benchmark suites within that group. Use `--targets help` to see available suites.

```bash
$ ./bench-runner --targets help
$ ./bench-runner --targets array_cmp
```

--------------------------------

### Streamly.Data.MutArray.unsafeGetIndex

Source: https://github.com/composewell/streamly/blob/master/core/docs/ApiChangelogs/0.2.2-0.3.0.txt

Unsafely gets a value from a specific index in a mutable array, with Unbox constraint.

```APIDOC
## Streamly.Data.MutArray.unsafeGetIndex

### Description
Unsafely gets a value from a specific index in a mutable array. Requires the element type `a` to have an `Unbox` instance. This operation is monadic and does not perform bounds checking.

### Method
Monadic Operation

### Endpoint
N/A

### Parameters
#### Path Parameters
N/A

#### Query Parameters
N/A

#### Request Body
N/A

### Request Example
N/A

### Response
#### Success Response (200)
- **m a** (type) - A monadic action that returns the value at the specified index.

#### Response Example
N/A
```

--------------------------------

### Build Project with Development Streamly Version

Source: https://github.com/composewell/streamly/blob/master/docs/User/Tutorials/using-streamly.md

After creating the `cabal.project` file, run `cabal repl` to fetch and build the development version of `streamly-core`.

```bash
$ cabal repl
Cloning into '/home/harendra/streamly-project/...
... In order, the following will be built (use -v for more details):
 - streamly-core-0.1.0 (lib:streamly-core) (requires build)
 - streamly-project-0.1.0.0 (exe:streamly-project) (configuration changed)
 ...
ghci>
```

--------------------------------

### Get the context of a data type

Source: https://github.com/composewell/streamly/blob/master/core/docs/ApiChangelogs/0.1.0-0.2.0.txt

Retrieves the type context associated with a data type.

```haskell
[dtCxt] :: DataType -> Cxt
```

--------------------------------

### Get the context of a data constructor

Source: https://github.com/composewell/streamly/blob/master/core/docs/ApiChangelogs/0.1.0-0.2.0.txt

Retrieves the type context associated with a data constructor.

```haskell
[dcCxt] :: DataCon -> Cxt
```

--------------------------------

### Compare Benchmark Suites

Source: https://github.com/composewell/streamly/blob/master/benchmark/README.md

Run comparison group benchmarks (ending in `_cmp`) to see comparisons of all benchmark suites within that group.

```bash
$ ./bench-runner --targets help

$ ./bench-runner --targets array_cmp
```

--------------------------------

### Streamly.Data.Stream stripPrefix

Source: https://github.com/composewell/streamly/blob/master/core/docs/ApiChangelogs/0.1.0.txt

Checks if a stream starts with a given prefix. Requires Monad and Eq constraints.

```APIDOC
## stripPrefix :: (Monad m, Eq a) => Stream m a -> Stream m a -> m (Maybe (Stream m a))

### Description
Checks if the first stream is a prefix of the second stream. If it is, returns Just the remainder of the second stream; otherwise, returns Nothing.

### Method
N/A (Function signature)

### Endpoint
N/A (Function signature)

### Parameters
#### Path Parameters
- **Stream m a** (Stream) - Required - The potential prefix stream.
- **Stream m a** (Stream) - Required - The stream to check.

### Response
#### Success Response
- **m (Maybe (Stream m a))** - A monadic value containing Maybe the remaining stream if the prefix matches, or Nothing.

### Request Example
N/A (Function signature)

### Response Example
N/A (Function signature)
```

--------------------------------

### Constructing Monadic Streams from IO Actions

Source: https://github.com/composewell/streamly/blob/master/docs/User/HowTo/streamly-vs-lists.md

Shows how to construct a stream using monadic IO actions like `getLine`. The actions are executed sequentially as the stream is consumed.

```haskell
>>> import qualified Streamly.Data.StreamK as StreamK
>>> StreamK.toList $ getLine `StreamK.cons` getLine `StreamK.cons` StreamK.nil
```

--------------------------------

### Build and Run a Single Test Suite using Cabal

Source: https://github.com/composewell/streamly/blob/master/docs/Developer/Tests.md

Compile and run a specific test suite, such as Prelude.Serial. Using 'cabal test' for a single suite may build all suites first.

```bash
$ cabal run test:Prelude.Serial
```

```bash
$ cd test; cabal run Prelude.Serial
```

--------------------------------

### Streamly.Data.Stream unfold

Source: https://github.com/composewell/streamly/blob/master/core/docs/ApiChangelogs/0.1.0.txt

Unfolds a stream from a starting value using an unfold. Requires Applicative constraint.

```APIDOC
## unfold :: Applicative m => Unfold m a b -> a -> Stream m b

### Description
Creates a stream by applying an unfold starting from an initial value.

### Method
N/A (Function signature)

### Endpoint
N/A (Function signature)

### Parameters
#### Path Parameters
- **Unfold m a b** (Unfold) - Required - The unfold to use.
- **a** (starting value) - Required - The initial value for the unfold.

### Response
#### Success Response
- **Stream m b** - The generated stream.

### Request Example
N/A (Function signature)

### Response Example
N/A (Function signature)
```

--------------------------------

### Get the constructors of a data type

Source: https://github.com/composewell/streamly/blob/master/core/docs/ApiChangelogs/0.1.0-0.2.0.txt

Retrieves the list of data constructors for a given data type.

```haskell
[dtCons] :: DataType -> [DataCon]
```

--------------------------------

### Initialize Haskell Project with Streamly Dependency

Source: https://github.com/composewell/streamly/blob/master/docs/User/Tutorials/using-streamly.md

Use `cabal init` to create a new Haskell project with `streamly-core` as a dependency. Ensure `base` is also listed.

```bash
$ cd streamly-project
$ cabal init --non-interactive --minimal --dependency base --dependency streamly-core
```

--------------------------------

### deserializePtrN

Source: https://github.com/composewell/streamly/blob/master/core/docs/ApiChangelogs/0.2.2-0.3.0.txt

Deserializes a value from a mutable array starting at a given pointer, returning the value and the remaining array.

```APIDOC
## deserializePtrN

### Description
Deserializes a value from a mutable array starting at a given pointer, returning the value and the remaining array.

### Method
MutArray Word8 -> (Ptr a -> Int -> m b) -> m (a, MutArray Word8)

### Parameters
#### Path Parameters
- **array** (MutArray Word8) - Required - The mutable array containing serialized data.
- **deserializer** (Ptr a -> Int -> m b) - Required - A function to perform the deserialization.

### Response
#### Success Response
- **m (a, MutArray Word8)** - A monadic action returning the deserialized value and the remaining mutable array.

```

--------------------------------

### Create and Upload Haddock Documentation

Source: https://github.com/composewell/streamly/blob/master/docs/Developer/MAINTAINING.md

Generate Haddock documentation for Hackage and upload it. Ensure the documentation is built with the correct flags.

```bash
cabal v2-haddock --haddock-for-hackage --enable-doc; cabal upload -d <tarpath>
```

--------------------------------

### Infinite Stream of Integers

Source: https://github.com/composewell/streamly/blob/master/docs/User/Tutorials/streams-as-loops.md

Defines an infinite stream of integers starting from 1. Requires importing Streamly.Data.Stream.

```haskell
>>> s2 = Stream.enumerateFrom 1 :: Stream IO Int
```

--------------------------------

### Basic Stream Operations in GHCi

Source: https://github.com/composewell/streamly/blob/master/docs/User/Tutorials/using-streamly.md

Demonstrates importing Streamly modules and performing basic stream operations like mapping and folding. It shows how to create a stream from a list, print each element, and drain the stream.

```haskell
ghci> import qualified Streamly.Data.Stream as Stream
ghci> import qualified Streamly.Data.Fold as Fold

ghci> Stream.fold Fold.drain $ Stream.mapM print $ Stream.fromList [1..3]
1
2
3
ghci>
```

--------------------------------

### Create and Push Git Tag for Release

Source: https://github.com/composewell/streamly/blob/master/docs/Developer/MAINTAINING.md

Create a Git tag for the release in the format P-X.Y.Z (where P is the package name) and push it to the origin. This is essential for version control and release tracking.

```bash
git tag P-X.Y.Z && git push -f origin P-X.Y.Z
```

--------------------------------

### Get type variables of a data type

Source: https://github.com/composewell/streamly/blob/master/core/docs/ApiChangelogs/0.1.0-0.2.0.txt

Retrieves the list of type variables associated with a data type.

```haskell
[dtTvs] :: DataType -> [Name]
```

--------------------------------

### Compile Benchmarks with Diagnostics

Source: https://github.com/composewell/streamly/blob/master/benchmark/README.md

Configure GHC options to dump simplification, suppress all but specific warnings, and enable verbose fusion plugin output for detailed diagnostics. This is done by commenting out other benchmarks and adding OPTIONS_GHC pragmas.

```haskell
{-# OPTIONS_GHC
  -ddump-simpl
  -ddump-to-file
  -dsuppress-all
  -Wmissed-specialisations
  -Wall-missed-specialisations
  -fplugin-opt=Fusion.Plugin:verbose=2
  -fplugin-opt=Fusion.Plugin:dump-core
#-}
```

--------------------------------

### Get type variables of a data constructor

Source: https://github.com/composewell/streamly/blob/master/core/docs/ApiChangelogs/0.1.0-0.2.0.txt

Retrieves the list of type variables associated with a data constructor.

```haskell
[dcTvs] :: DataCon -> [Name]
```

--------------------------------

### Get Contributors Between Tags

Source: https://github.com/composewell/streamly/blob/master/docs/User/Project/CONTRIBUTORS.md

Use this git command to list contributors between two specific tags in the repository.

```bash
git shortlog -sn tag1...tag2
```

--------------------------------

### Specify External Input File for FileSystem.Handle Benchmark

Source: https://github.com/composewell/streamly/blob/master/benchmark/README.md

Set the Benchmark_FileSystem_Handle_InputFile environment variable to specify an input file for the FileSystem.Handle benchmark, useful for testing unicode input.

```bash
$ export Benchmark_FileSystem_Handle_InputFile=./gutenberg-500.txt
$ cabal run FileSystem.Handle -- FileSystem.Handle/o-1-space/reduce/read/S.splitOnSeq
```

--------------------------------

### Generate Dependency Graph with Nix

Source: https://github.com/composewell/streamly/blob/master/docs/Developer/MAINTAINING.md

Generates a PDF of the dependency graph using nix. Remove test and benchmark components from shellFor/packages in default.nix for library-only dependencies.

```bash
nix-shell --run "ghc-pkg dot | dot -Tpdf > streamly.pdf"
```

--------------------------------

### Recommended GHC Compilation Options

Source: https://github.com/composewell/streamly/blob/master/docs/User/HowTo/Compiling.md

These GHC options are recommended for optimal performance when using the fusion-plugin. Ensure 'fusion-plugin' is added to your cabal file's build-depends.

```text
-O2
-fdicts-strict
-fmax-worker-args=16
-fspec-constr-recursive=16
-fplugin Fusion.Plugin
```

--------------------------------

### Get inline deserialization setting

Source: https://github.com/composewell/streamly/blob/master/core/docs/ApiChangelogs/0.1.0-0.2.0.txt

Retrieves the 'cfgInlineDeserialize' setting from a 'SerializeConfig'. Indicates whether to inline deserialization logic.

```haskell
[cfgInlineDeserialize] :: SerializeConfig -> Maybe Inline
```