@stdlib/array/mostly-safe-casts/README.md

Arrays.

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# Mostly Safe Casts

> Return a list of array [data types][@stdlib/array/dtypes] to which a provided array [data type][@stdlib/array/dtypes] can be safely cast and, for floating-point data types, can be downcast.

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## Usage

```javascript
var mostlySafeCasts = require( '@stdlib/array/mostly-safe-casts' );
```

#### mostlySafeCasts( \[dtype] )

If provided a `dtype` argument, returns a list of array [data types][@stdlib/array/dtypes] to which a provided array [data type][@stdlib/array/dtypes] can be safely cast and, for floating-point data types, can be downcast.

```javascript
var out = mostlySafeCasts( 'float32' );
// e.g., returns [ 'float32', 'float64', ... ]
```

If not provided a `dtype` argument, the function returns a casting table.

```javascript
var out = mostlySafeCasts();
// returns {...}

var f32 = out[ 'float32' ];
// returns {...}

var v = f32[ 'float64' ];
// returns 1
```

If provided an unrecognized or unsupported `dtype`, the function returns `null`.

```javascript
var out = mostlySafeCasts( 'foo' );
// returns null
```

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## Examples

<!-- eslint no-undef: "error" -->

```javascript
var dtypes = require( '@stdlib/array/dtypes' );
var mostlySafeCasts = require( '@stdlib/array/mostly-safe-casts' );

// Get the list of supported array data types:
var DTYPES = dtypes();

// Print the list of array data types to which a data type can be cast...
var list;
var i;
for ( i = 0; i < DTYPES.length; i++ ) {
    list = mostlySafeCasts( DTYPES[ i ] );
    console.log( '%s: %s', DTYPES[ i ], list.join( ', ' ) );
}
```

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* * *

## See Also

-   <span class="package-name">[`@stdlib/array/convert`][@stdlib/array/convert]</span><span class="delimiter">: </span><span class="description">convert an array to an array of a different data type.</span>
-   <span class="package-name">[`@stdlib/array/convert-same`][@stdlib/array/convert-same]</span><span class="delimiter">: </span><span class="description">convert an array to the same data type as a second input array.</span>
-   <span class="package-name">[`@stdlib/array/dtypes`][@stdlib/array/dtypes]</span><span class="delimiter">: </span><span class="description">list of array data types.</span>
-   <span class="package-name">[`@stdlib/array/safe-casts`][@stdlib/array/safe-casts]</span><span class="delimiter">: </span><span class="description">return a list of array data types to which a provided array data type can be safely cast.</span>
-   <span class="package-name">[`@stdlib/array/same-kind-casts`][@stdlib/array/same-kind-casts]</span><span class="delimiter">: </span><span class="description">return a list of array data types to which a provided array data type can be safely cast or cast within the same kind.</span>
-   <span class="package-name">[`@stdlib/ndarray/mostly-safe-casts`][@stdlib/ndarray/mostly-safe-casts]</span><span class="delimiter">: </span><span class="description">return a list of ndarray data types to which a provided ndarray data type can be safely cast and, for floating-point data types, can be downcast.</span>

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[@stdlib/array/dtypes]: https://github.com/stdlib-js/array/tree/main/dtypes

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[@stdlib/array/convert]: https://github.com/stdlib-js/array/tree/main/convert

[@stdlib/array/convert-same]: https://github.com/stdlib-js/array/tree/main/convert-same

[@stdlib/array/safe-casts]: https://github.com/stdlib-js/array/tree/main/safe-casts

[@stdlib/array/same-kind-casts]: https://github.com/stdlib-js/array/tree/main/same-kind-casts

[@stdlib/ndarray/mostly-safe-casts]: https://www.npmjs.com/package/@stdlib/ndarray-mostly-safe-casts

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