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Add .isEmpty term entry for Dart Map #8125
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c828324
Add .isEmpty term entry for Dart Map
omkarhole 16e44ec
Refine Dart Map .isEmpty documentation
omkarhole 96fea9a
Clarify parameter name in isEmpty documentation
omkarhole 4b46277
Update is-empty.md
omkarhole b117073
Merge branch 'main' into dart-map-isempty-term
omkarhole 69421be
Clarify .isEmpty property usage in Maps
mamtawardhani File filter
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| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,80 @@ | ||
| --- | ||
| Title: '.isEmpty' | ||
| Description: 'Checks if a Map contains no key-value pairs.' | ||
| Subjects: | ||
| - 'Computer Science' | ||
| - 'Code Foundations' | ||
| Tags: | ||
| - 'Dart' | ||
| - 'Map' | ||
| - 'Properties' | ||
| CatalogContent: | ||
| - 'learn-dart' | ||
| - 'paths/computer-science' | ||
| --- | ||
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| In Dart, the **`.isEmpty`** property is used to check if a `Map` contains no key-value pairs. It evaluates to `true` when the map’s length is zero and `false` otherwise. | ||
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| ## Syntax | ||
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| ```pseudo | ||
| map.isEmpty | ||
| ``` | ||
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| **Parameters:** | ||
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| This property takes no parameters. | ||
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| **Return value:** | ||
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| Returns a boolean value: | ||
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| - `true` if the map contains no key–value pairs | ||
| - `false` if the map contains one or more entries | ||
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| ## Example 1: Checking if a Map Is Empty | ||
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| In this example, `.isEmpty` is used to check the state of an empty map and a populated map: | ||
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| ```dart | ||
| void main() { | ||
| // Creating an empty Map | ||
| Map<String, int> emptyCart = {}; | ||
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| // Creating a Map with items | ||
| Map<String, int> fruitCart = {'Apple': 3, 'Banana': 5}; | ||
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| // Checking if the maps are empty | ||
| print(emptyCart.isEmpty); | ||
| print(fruitCart.isEmpty); | ||
| } | ||
| ``` | ||
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| The above example produces the following output: | ||
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| ```shell | ||
| true | ||
| false | ||
| ``` | ||
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| ## Example 2: Using .isEmpty in a Conditional Check | ||
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| In this example, `.isEmpty` controls program flow by checking whether a map contains data before accessing it: | ||
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| ```dart | ||
| void main() { | ||
| Map<String, String> userInfo = {}; | ||
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| if (userInfo.isEmpty) { | ||
| print('No user data available.'); | ||
| } else { | ||
| print('User data found.'); | ||
| } | ||
| } | ||
| ``` | ||
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| The above example produces the following output: | ||
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| ```shell | ||
| No user data available. | ||
| ``` | ||
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