Pipeline Terminator - Assertions

In this section, we’ll explore how to use assertion terminators in Pipeline. We’ll use items model for this example.

GML

var schema = {
    id: {
        type: NIMBUSDB_DATA_TYPE.INTEGER,
        const: NIMBUSDB_CONSTRAINT.PRIMARY_KEY
    },
    name: NIMBUSDB_DATA_TYPE.STRING,
    price: {
        type: NIMBUSDB_DATA_TYPE.NUMBER,
        validator: function(data, value) {
            return value >= 0;
        },
        default_value: 0
    },
    is_locked: {
        type: NIMBUSDB_DATA_TYPE.BOOLEAN,
        const: NIMBUSDB_CONSTRAINT.OPTIONAL,
        default_value: false
    }
};

items = new NimbusDBModel("global", "items", schema, [
    { id: 1, name: "Apple", price: 5 },
    { id: 2, name: "Banana", price: 7.2 },
    { id: 3, name: "Cherry", price: 15 },
    { id: 4, name: "Date", price: 12.5 },
    { id: 5, name: "Elderberry", price: 8 },
    { id: 6, name: "Fig", price: 10 },
    { id: 7, name: "Grape", price: 6 },
    { id: 8, name: "Honeydew", price: 9 },
    { id: 9, name: "Kiwi", price: 4 },
    { id: 10, name: "Lemon", price: 3 }
]);

Assertions

It means to check if the pipeline result meets the specified condition.

Every Array

The every method checks if all elements in the pipeline result meet the specified condition.

GML

var items_pl = items.pipe().isolate()
    .filter(function(data, index) {     // include only items with `price` greater than or equal to 8
        return data.price >= 8;
    })
    .limit(3)                           // limit the result to 3 items
    .map(function(data, index) {        // map the result to an array of strings
        return data.name;
    });

var result = items_pl.every(function(data, index) {
    return string_length(data) >= 5;
});
show_debug_message($"Result: {result}");

// Result: false

Some Array

The some method checks if at least one element in the pipeline result meets the specified condition.

GML

var items_pl = items.pipe().isolate()
    .filter(function(data, index) {     // include only items with `price` greater than or equal to 8
        return data.price >= 8;
    })
    .limit(3)                           // limit the result to 3 items
    .map(function(data, index) {        // map the result to an array of strings
        return data.name;
    });

var result = items_pl.some(function(data, index) {
    return string_length(data) >= 5;
});
show_debug_message($"Result: {result}");

// Result: true

Includes Array

The includes method checks if the pipeline result contains the specified element.

GML

var items_pl = items.pipe().isolate()
    .filter(function(data, index) {     // include only items with `price` greater than or equal to 8
        return data.price >= 8;
    })
    .limit(3)                           // limit the result to 3 items
    .map(function(data, index) {        // map the result to an array of strings
        return data.name;
    });

var result = items_pl.includes("Cherry");
show_debug_message($"Result: {result}");

// Result: true

Index of Array

The index_of method returns the index of the first occurrence of the specified element in the pipeline result.

GML

var items_pl = items.pipe().isolate()
    .filter(function(data, index) {     // include only items with `price` greater than or equal to 8
        return data.price >= 8;
    })
    .limit(3)                           // limit the result to 3 items
    .map(function(data, index) {        // map the result to an array of strings
        return data.name;
    });

var result = items_pl.index_of("Date");
show_debug_message($"Result: {result}");

// Result: 1

Note

If the specified element is not found, the index_of method returns -1.

Is Empty Array

The is_empty method checks if the pipeline result is empty.

GML

var items_pl = items.pipe().isolate()
    .filter(function(data, index) {     // include only items with `price` greater than or equal to 8
        return data.price >= 8;
    })
    .limit(3)                           // limit the result to 3 items
    .map(function(data, index) {        // map the result to an array of strings
        return data.name;
    });

var result = items_pl.is_empty();
show_debug_message($"Result: {result}");

// Result: false

---

References

Pipeline.every()

Returns true if every element at the given cursor position satisfies the condition.

Overload 1

Signature

pipeline.d.ts

class NimbusDBPipeline {
    // ... other methods and properties ...
    static every(
        _func: (element: any, index: int) => boolean,
        _options?: NimbusDBPipelineTerminalOptions
    ): boolean;
}

Parameters

_func

• Type: (element: any, index: int) => boolean
  • Parameters:
    • element: The current element.
    • index: The current index.
  • Returns: true if the condition is met, false otherwise.
• The condition function to use for the every operation.

_options

• Type: NimbusDBPipelineTerminalOptions
• Default: undefined
• An optional object that allows you to customize the behavior of the every operation.

Returns

• Type: boolean
• The result of the every operation.

Overload 2

Signature

pipeline.d.ts

class NimbusDBPipeline {
    // ... other methods and properties ...
    static every(
        _pos: int,
        _func: (element: any, index: int) => boolean,
        _options?: NimbusDBPipelineTerminalOptions
    ): boolean;
}

Parameters

_pos

• Type: int
• The cursor position used as the end of the pipeline operations.

_func

• Type: (element: any, index: int) => boolean
  • Parameters:
    • element: The current element.
    • index: The current index.
  • Returns: true if the condition is met, false otherwise.
• The condition function to use for the every operation.

_options

• Type: NimbusDBPipelineTerminalOptions
• Default: undefined
• An optional object that allows you to customize the behavior of the every operation.

Returns

• Type: boolean
• The result of the every operation.

Pipeline.includes()

Checks if the pipeline result contains the specified element.

Overload 1

Signature

pipeline.d.ts

class NimbusDBPipeline {
    // ... other methods and properties ...
    static includes(
        _value: any,
        _options?: NimbusDBPipelineTerminalOptions
    ): boolean;
}

Parameters

_value

• Type: any
• The value to search for.

_options

• Type: NimbusDBPipelineTerminalOptions
• Default: undefined
• An optional object that allows you to customize the behavior of the includes operation.

Returns

• Type: boolean
• The result of the includes operation.

Overload 2

Signature

pipeline.d.ts

class NimbusDBPipeline {
    // ... other methods and properties ...
    static includes(
        _value: any,
        _pos?: int,
        _options?: NimbusDBPipelineTerminalOptions
    ): boolean;
}

Parameters

_value

• Type: any
• The value to search for.

_pos

• Type: int
• The cursor position used as the end of the pipeline operations.

_options

• Type: NimbusDBPipelineTerminalOptions
• Default: undefined
• An optional object that allows you to customize the behavior of the includes operation.

Returns

• Type: boolean
• The result of the includes operation.

Pipeline.index_of()

Finds the index of an element matching a value or predicate function.

Overload 1

Signature

pipeline.d.ts

class NimbusDBPipeline {
    // ... other methods and properties ...
    static index_of(
        _value: any,
        _options?: NimbusDBPipelineTerminalOptions
    ): int;
}

Parameters

_value

• Type: any
• The value to search for.

_options

• Type: NimbusDBPipelineTerminalOptions
• Default: undefined
• An optional object that allows you to customize the behavior of the index_of operation.

Returns

• Type: int
• The result of the index_of operation.

Overload 2

Signature

pipeline.d.ts

class NimbusDBPipeline {
    // ... other methods and properties ...
    static index_of(
        _value: any,
        _pos?: int,
        _options?: NimbusDBPipelineTerminalOptions
    ): int;
}

Parameters

_value

• Type: any
• The value to search for.

_pos

• Type: int
• The cursor position used as the end of the pipeline operations.

_options

• Type: NimbusDBPipelineTerminalOptions
• Default: undefined
• An optional object that allows you to customize the behavior of the index_of operation.

Returns

• Type: int
• The result of the index_of operation.

Pipeline.is_empty()

Checks whether the pipeline data at the given cursor position is empty.

Signature

pipeline.d.ts

class NimbusDBPipeline {
    // ... other methods and properties ...
    static is_empty(
        _pos?: int,
        _options?: NimbusDBPipelineTerminalOptions
    ): boolean;
}

Parameters

_pos

• Type: int
• Default: -1 (the last step)
• The cursor position used as the end of the pipeline operations.

_options

• Type: NimbusDBPipelineTerminalOptions
• Default: undefined
• An optional object that allows you to customize the behavior of the is_empty operation.

Returns

• Type: boolean
• The result of the is_empty operation.

Pipeline.some()

Returns true if at least one element satisfies the condition.

Overload 1

Signature

pipeline.d.ts

class NimbusDBPipeline {
    // ... other methods and properties ...
    static some(
        _func: (element: any, index: int) => boolean,
        _options?: NimbusDBPipelineTerminalOptions
    ): boolean;
}

Parameters

_func

• Type: (element: any, index: int) => boolean
  • Parameters:
    • element: The current element.
    • index: The current index.
  • Returns: true if the condition is met, false otherwise.
• The condition function to use for the some operation.

_options

• Type: NimbusDBPipelineTerminalOptions
• Default: undefined
• An optional object that allows you to customize the behavior of the some operation.

Returns

• Type: boolean
• The result of the some operation.

Overload 2

Signature

pipeline.d.ts

class NimbusDBPipeline {
    // ... other methods and properties ...
    static some(
        _pos: int,
        _func: (element: any, index: int) => boolean,
        _options?: NimbusDBPipelineTerminalOptions
    ): boolean;
}

Parameters

_pos

• Type: int
• The cursor position used as the end of the pipeline operations.

_func

• Type: (element: any, index: int) => boolean
  • Parameters:
    • element: The current element.
    • index: The current index.
  • Returns: true if the condition is met, false otherwise.
• The condition function to use for the some operation.

_options

• Type: NimbusDBPipelineTerminalOptions
• Default: undefined
• An optional object that allows you to customize the behavior of the some operation.

Returns

• Type: boolean
• The result of the some operation.