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Null additions (#73)
* feat(null): add getWithDefault, getExn, getUnsafe, map, mapWithDefault, flatMap * docs(null): Null.null -> null * docs(nullable): Nullable.undefined -> undefined * docs(changelog): add changelog entry for Null additions
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‎CHANGELOG.md‎

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- Change `Float.fromString` signature. Now accepts only string. https://github.com/rescript-association/rescript-core/pull/54
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- Change `Float.parseFloat` signature. Now accepts only string. https://github.com/rescript-association/rescript-core/pull/54
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- Add `getExn`, `getUnsafe`, `getWithDefault`, `map`, `mapWithDefault` and `flatMap` to `Nullable`. https://github.com/rescript-association/rescript-core/pull/67
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- Add `getExn`, `getUnsafe`, `getWithDefault`, `map`, `mapWithDefault` and `flatMap` to `Null`. https://github.com/rescript-association/rescript-core/pull/73
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### Documentation
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‎src/Core__Null.mjs‎

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// Generated by ReScript, PLEASE EDIT WITH CARE
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import * as Curry from "rescript/lib/es6/curry.js";
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import * as Caml_option from "rescript/lib/es6/caml_option.js";
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function fromOption(option) {
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}
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}
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function getWithDefault(value, $$default) {
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if (value !== null) {
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return value;
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} else {
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return $$default;
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}
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}
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function getExn(value) {
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if (value !== null) {
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return value;
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}
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throw {
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RE_EXN_ID: "Invalid_argument",
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_1: "Null.getExn: value is null",
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Error: new Error()
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};
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}
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function map(value, f) {
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if (value !== null) {
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return Curry._1(f, value);
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} else {
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return null;
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}
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}
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function mapWithDefault(value, $$default, f) {
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if (value !== null) {
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return Curry._1(f, value);
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} else {
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return $$default;
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}
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}
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function flatMap(value, f) {
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if (value !== null) {
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return Curry._1(f, value);
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} else {
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return null;
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}
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}
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export {
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fromOption ,
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getWithDefault ,
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getExn ,
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map ,
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mapWithDefault ,
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flatMap ,
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}
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/* No side effect */

‎src/Core__Null.res‎

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| Some(x) => make(x)
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| None => null
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}
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let getWithDefault = (value, default) =>
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switch value->toOption {
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| Some(x) => x
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| None => default
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}
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let getExn: t<'a> => 'a = value =>
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switch value->toOption {
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| Some(x) => x
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| None => raise(Invalid_argument("Null.getExn: value is null"))
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}
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external getUnsafe: t<'a> => 'a = "%identity"
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let map = (value, f) =>
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switch value->toOption {
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| Some(x) => make(f(x))
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| None => null
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}
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let mapWithDefault = (value, default, f) =>
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switch value->toOption {
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| Some(x) => f(x)
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| None => default
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}
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let flatMap = (value, f) =>
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switch value->toOption {
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| Some(x) => f(x)
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| None => null
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}

‎src/Core__Null.resi‎

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@@ -27,7 +27,7 @@ See [`null`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/O
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## Examples
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```rescript
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Console.log(Null.null) // Logs `null` to the console.
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Console.log(null) // Logs `null` to the console.
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```
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*/
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external null: t<'a> = "#null"
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```rescript
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let optString: option<string> = None
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let asNull = optString->Null.fromOption // Null.t<string>
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Console.log(asNull == Null.null) // Logs `true` to the console.
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Console.log(asNull == null) // Logs `true` to the console.
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```
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*/
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let fromOption: option<'a> => t<'a>
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/**
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`getWithDefault(value, default)` returns `value` if not `null`, otherwise return
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`default`.
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## Examples
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```rescript
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Null.getWithDefault(null, "Banana") // Banana
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Null.getWithDefault(Nulalble.make("Apple"), "Banana") // Apple
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let greet = (firstName: option<string>) =>
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"Greetings " ++ firstName->Null.getWithDefault("Anonymous")
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Null.make("Jane")->greet // "Greetings Jane"
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null->greet // "Greetings Anonymous"
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```
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*/
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let getWithDefault: (t<'a>, 'a) => 'a
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/**
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`getExn(value)` raises an exception if `null`, otherwise returns the value.
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```rescript
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Null.getExn(Null.make(3)) // 3
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Null.getExn(null) /* Raises an Error */
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```
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## Exceptions
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- Raises `Invalid_argument` if `value` is `null`,
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*/
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let getExn: t<'a> => 'a
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/**
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`getUnsafe(value)` returns `value`.
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## Examples
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```rescript
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Null.getUnsafe(Null.make(3)) == 3
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Null.getUnsafe(null) // Raises an error
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```
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## Important
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- This is an unsafe operation, it assumes `value` is not `null`.
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*/
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external getUnsafe: t<'a> => 'a = "%identity"
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/**
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`map(value, f)` returns `f(value)` if `value` is not `null`, otherwise returns
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`value` unchanged.
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## Examples
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```rescript
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Null.map(Null.make(3), x => x * x) // Null.make(9)
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Null.map(null, x => x * x) // null
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```
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*/
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let map: (t<'a>, 'a => 'b) => t<'b>
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/**
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`mapWithDefault(value, default, f)` returns `f(value)` if `value` is not `null`,
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otherwise returns `default`.
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## Examples
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```rescript
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let someValue = Null.make(3)
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someValue->Null.mapWithDefault(0, x => x + 5) // 8
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let noneValue = null
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noneValue->Null.mapWithDefault(0, x => x + 5) // 0
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```
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*/
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let mapWithDefault: (t<'a>, 'b, 'a => 'b) => 'b
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/**
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`flatMap(value, f)` returns `f(value)` if `value` is not `null`, otherwise
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returns `value` unchanged.
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## Examples
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```rescript
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let addIfAboveOne = value =>
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if (value > 1) {
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Null.make(value + 1)
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} else {
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null
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}
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Null.flatMap(Null.make(2), addIfAboveOne) // Null.make(3)
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Null.flatMap(Null.make(-4), addIfAboveOne) // null
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Null.flatMap(null, addIfAboveOne) // null
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```
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*/
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let flatMap: (t<'a>, 'a => t<'b>) => t<'b>

‎src/Core__Nullable.resi‎

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## Examples
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```rescript
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Console.log(Nullable.undefined) // Logs `undefined` to the console.
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Console.log(undefined) // Logs `undefined` to the console.
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```
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*/
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external undefined: t<'a> = "#undefined"
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```rescript
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Nullable.map(Nullable.make(3), x => x * x) // Nullable.make(9)
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Nullable.map(Nullable.undefined, x => x * x) // Nullable.undefined
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Nullable.map(undefined, x => x * x) // undefined
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```
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*/
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let map: (t<'a>, 'a => 'b) => t<'b>
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}
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Nullable.flatMap(Nullable.make(2), addIfAboveOne) // Nullable.make(3)
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Nullable.flatMap(Nullable.make(-4), addIfAboveOne) // Nullable.undefined
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Nullable.flatMap(Nullable.null, addIfAboveOne) // Nullable.undefined
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Nullable.flatMap(Nullable.make(-4), addIfAboveOne) // undefined
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Nullable.flatMap(Nullable.null, addIfAboveOne) // undefined
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```
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*/
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let flatMap: (t<'a>, 'a => t<'b>) => t<'b>

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