···

       
28
       
 
       
It exposes a set of helpers to create and transform sources and output sinks, meaning it helps you to turn an event source or an

     

       
29
       
 
       
iterable set of data into streams, and manipulate these streams.

     

       
30
       
 
       


     

       
31
       
-
       
## Why it exists

     

       
32
       
-
       


     

       
33
       
 
       
Reason has been becoming increasingly popular, but it's missing a good pattern for streams that feels native to the language.

     

       
34
       
 
       
The functional nature of callbags make them a perfect starting point to fix this, and to introduce a reactive programming

     

       
35
       
 
       
pattern to a language that is well suited for it.

     

       
36
       
 
       


     

       
37
       
-
       
Hence `Wonka` is a library that aims to make complex streams of data easy to deal with.

     

       
0
       
 
       

     

       
0
       
 
       

     

       
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38
       
 
       


     

       
39
       
 
       
## Installation

     

       
40
       
 
       


     

       
41
       
 
       
Install the library first: `yarn add wonka` or `npm install --save wonka`,

     

       
42
       
 
       


     

       
43
       
-
       
Then add `wonka` to `bs-dependencies` in your `bsconfig.json` file like so:

     

       
0
       
 
       

     

       
0
       
 
       

     

       
44
       
 
       


     

       
45
       
 
       
```diff

     

       
46
       
 
       
{

     
···

       
54
       
 
       
}

     

       
55
       
 
       
```

     

       
56
       
 
       


     

       
57
       
-
       
## Getting Started

     

       
58
       
-
       


     

       
59
       
-
       
Writing your first stream is very easy! Let's suppose you would like to create a stream from a list, filter out some values,

     

       
60
       
-
       
then map over the remaining ones, and lastly iterate over the final values.

     

       
61
       
-
       


     

       
62
       
-
       
This can be done with a few operators that might remind you of functions you would also call on iterables.

     

       
63
       
-
       


     

       
64
       
-
       
```reason

     

       
65
       
-
       
let example = [1, 2, 3, 4, 5, 6];

     

       
66
       
-
       


     

       
67
       
-
       
Wonka.fromList(example)

     

       
68
       
-
       
  |> Wonka.filter((.x) => x mod 2 === 0)

     

       
69
       
-
       
  |> Wonka.map((.x )=> x * 2)

     

       
70
       
-
       
  |> Wonka.forEach((.x) => print_endline(string_of_int(x)));

     

       
71
       
-
       


     

       
72
       
-
       
/* prints: 4, 8, 12 */

     

       
73
       
-
       
```

     

       
74
       
-
       


     

       
75
       
-
       
To explain what's going on:

     

       
76
       
-
       


     

       
77
       
-
       
- `fromList` creates a pullable source with values from the list

     

       
78
       
-
       
- `filter` only lets even values through

     

       
79
       
-
       
- `map` multiplies the values by `2`

     

       
80
       
-
       
- `forEach` pulls values from the resulting source and prints them

     

       
81
       
-
       


     

       
82
       
-
       
As you can see, all helpers that we've used are exposed on the `Wonka` module.

     

       
83
       
-
       
But if we would like to use JavaScript-based APIs, then we need to use the `WonkaJs` module.

     

       
84
       
-
       


     

       
85
       
-
       
Let's look at the same example, but instead of a list we will use an `interval` stream.

     

       
86
       
-
       
This stream will output ascending numbers starting from `0` indefinitely.

     

       
87
       
-
       


     

       
88
       
-
       
We will code the same example as before but we'd like the `interval` to push

     

       
89
       
-
       
a new number every `50ms` and to stop after seven values.

     

       
90
       
-
       


     

       
91
       
-
       
```reason

     

       
92
       
-
       
WonkaJs.interval(50)

     

       
93
       
-
       
  |> Wonka.take(7)

     

       
94
       
-
       
  |> Wonka.filter((.x) => x mod 2 === 0)

     

       
95
       
-
       
  |> Wonka.map((.x) => x * 2)

     

       
96
       
-
       
  |> Wonka.forEach((.x) => print_endline(string_of_int(x)));

     

       
97
       
-
       


     

       
98
       
-
       
/* prints: 4, 8, 12 */

     

       
99
       
-
       
```

     

       
100
       
-
       


     

       
101
       
-
       
The last three functions stay the same, but we are now using `interval` as our source.

     

       
102
       
-
       
This is a listenable source, meaning that it pushes values downwards when it sees fit.

     

       
103
       
-
       
And the `take` operator tells our source to stop sending values after having received seven

     

       
104
       
-
       
values.

     

       
105
       
-
       


     

       
106
       
-
       
And already you have mastered all the basics of `Wonka` and learned about a couple of its operators!

     

       
107
       
-
       
Go, you! :tada:

     

       
108
       
-
       


     

       
109
       
 
       
## Documentation

     

       
110
       
 
       


     

       
111
       
-
       
I am currently still working on getting some documentation up and running. Those will contain:

     

       
0
       
 
       

     

       
112
       
 
       


     

       
113
       
 
       
- The API, i.e. a list of all helpers

     

       
114
       
 
       
- Examples

     
···

       
116
       
 
       
- Developer Guides (How to write a source/operator/sink)

     

       
117
       
 
       
- Modified Callbag spec

     

       
118
       
 
       


     

       
119
       
-
       
Stay tuned and read the signature files in the meantime please:

     

       
120
       
-
       


     

       
121
       
-
       
- [wonka.rei](./src/wonka.rei)

     

       
122
       
-
       
- [wonkaJs.rei](./src/wonka.rei)

     

       
123
       
-
       


     

···

       
28
       
 
       
It exposes a set of helpers to create and transform sources and output sinks, meaning it helps you to turn an event source or an

     

       
29
       
 
       
iterable set of data into streams, and manipulate these streams.

     

       
30
       
 
       


     

       
0
       
 
       

     

       
0
       
 
       

     

       
31
       
 
       
Reason has been becoming increasingly popular, but it's missing a good pattern for streams that feels native to the language.

     

       
32
       
 
       
The functional nature of callbags make them a perfect starting point to fix this, and to introduce a reactive programming

     

       
33
       
 
       
pattern to a language that is well suited for it.

     

       
34
       
 
       


     

       
35
       
+
       
This library also attempts to support as many Reason/JS environments as possible, which makes the adoption of streams across

     

       
36
       
+
       
multiple projects a lot easier.  Hence `Wonka` is a library that aims to make complex streams of data easy to deal with.

     

       
37
       
+
       


     

       
38
       
+
       
## Compatibility

     

       
39
       
+
       


     

       
40
       
+
       
`Wonka` is not only compatible with Reason/Bucklescript, but out of the box with other environments as well.

     

       
41
       
+
       


     

       
42
       
+
       
- TypeScript

     

       
43
       
+
       
- JS/Flow

     

       
44
       
+
       
- Reason/OCaml Bucklescript

     

       
45
       
+
       
- Reason/OCaml `bs-native`

     

       
46
       
+
       
- Reason/OCaml Dune

     

       
47
       
+
       


     

       
48
       
+
       
In summary, it should work in any TypeScript/Flow/Reason/OCaml environment with full type safety.

     

       
49
       
 
       


     

       
50
       
 
       
## Installation

     

       
51
       
 
       


     

       
52
       
 
       
Install the library first: `yarn add wonka` or `npm install --save wonka`,

     

       
53
       
 
       


     

       
54
       
+
       
### BuckleScript

     

       
55
       
+
       


     

       
56
       
+
       
For Bucklescript you will also need to add `wonka` to `bs-dependencies` in your `bsconfig.json` file like so:

     

       
57
       
 
       


     

       
58
       
 
       
```diff

     

       
59
       
 
       
{

     
···

       
67
       
 
       
}

     

       
68
       
 
       
```

     

       
69
       
 
       


     

       
0
       
 
       

     

       
0
       
 
       

     

       
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0
       
 
       

     

       
0
       
 
       

     

       
0
       
 
       

     

       
0
       
 
       

     

       
0
       
 
       

     

       
0
       
 
       

     

       
0
       
 
       

     

       
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0
       
 
       

     

       
70
       
 
       
## Documentation

     

       
71
       
 
       


     

       
72
       
+
       
This is still a work-in-progress but will contain full information on the following

     

       
73
       
+
       
across all supported languages:

     

       
74
       
 
       


     

       
75
       
 
       
- The API, i.e. a list of all helpers

     

       
76
       
 
       
- Examples

     
···

       
78
       
 
       
- Developer Guides (How to write a source/operator/sink)

     

       
79
       
 
       
- Modified Callbag spec

     

       
80
       
 
       


     

       
0
       
 
       

     

       
0
       
 
       

     

       
0
       
 
       

     

       
0
       
 
       

     

       
0