@use "sass:math";
@use "sass:meta";
@use "sass:string";

/*
---
name: is-int()
category:
  - core/function
  - core/function/condition
---
Checks for a valid int

### scss
```scss
//
// @param   mixed  $value
// @return  bool
//

@use "node_modules/sass-basis/src/css/core";

@if (core.is-int($value)) {
  z-index: $value;
}
```
*/
@function is-int($value) {
  @if ('number' == meta.type-of($value) and '' == math.unit($value) and $value == math.ceil($value) and $value == math.abs($value)) {
    @return true;
  }

  @return false;
}

/*
---
name: is-length()
category:
  - core/function
  - core/function/condition
---
Checks for a valid CSS length

### scss
```scss
//
// @param   mixed  $value
// @return  bool
//

@use "node_modules/sass-basis/src/css/core";

@if (core.is-length($value)) {
  width: $value;
}
```
*/

@function is-length($value) {
  @if ('auto' == $value) {
    @return true;
  }

  @if ('number' == meta.type-of($value)) {
    @if ('' != math.unit($value) or 0 == $value) {
      @return true;
    }
  }

  @if ('string' == meta.type-of($value)) {
    @if (1 == string.index($value, 'calc')) {
      @return true;
    }
  }

  @return false;
}

/*
---
name: is-null()
category:
  - core/function
  - core/function/condition
---
Checks for a valid null

### scss
```scss
//
// @param   mixed  $value
// @return  bool
//

@use "node_modules/sass-basis/src/css/core";

@if (not core.is-null($value)) {
  width: $value;
}
```
*/

@function is-null($value) {
  @if ('null' == meta.type-of($value)) {
    @return true;
  }

  @return false;
}

/*
---
name: is-number()
category:
  - core/function
  - core/function/condition
---
Checks for a valid number

### scss
```scss
//
// @param   mixed  $value
// @return  bool
//

@use "node_modules/sass-basis/src/css/core";

@if (core.is-number($value)) {
  z-index: $value;
}
```
*/

@function is-number($value) {
  @if ('number' == meta.type-of($value) and '' == math.unit($value)) {
    @return true;
  }

  @return false;
}