QGIS/resources/function_help/json/array_slice

{
        "name": "array_slice",
        "type": "function",
        "description": "Returns a portion of the array. The slice is defined by the start_pos and end_pos arguments.",
        "arguments": [{
                        "arg": "array",
                        "description": "an array"
                },
                {
                        "arg": "start_pos",
                        "description": "the index of the start position of the slice (0 based). The start_pos index is included in the slice. If you use a negative start_pos, the index is counted from the end of the list (-1 based)."
                },
                {
                        "arg": "end_pos",
                        "description": "the index of the end position of the slice (0 based). The end_pos index is included in the slice. If you use a negative end_pos, the index is counted from the end of the list (-1 based)."
                }
        ],
        "examples": [{
                        "expression": "array_slice(array(1,2,3,4,5),0,3)",
                        "returns": "array: 1,2,3,4"
                },
                {
                        "expression": "array_slice(array(1,2,3,4,5),0,-1)",
                        "returns": "array: 1,2,3,4,5"
                },
                {
                        "expression": "array_slice(array(1,2,3,4,5),-5,-1)",
                        "returns": "array: 1,2,3,4,5"
                },
                {
                        "expression": "array_slice(array(1,2,3,4,5),0,0)",
                        "returns": "array: 1"
                },
                {
                        "expression": "array_slice(array(1,2,3,4,5),-2,-1)",
                        "returns": "array: 4,5"
                },
                {
                        "expression": "array_slice(array(1,2,3,4,5),-1,-1)",
                        "returns": "array: 5"
                },
                {
                        "expression": "array_slice(array('Dufour','Valmiera','Chugiak','Brighton'),1,2)",
                        "returns": "array: 'Valmiera','Chugiak'"
                },
                {
                        "expression": "array_slice(array_slice(array('Dufour','Valmiera','Chugiak','Brighton'),-2,-1)",
                        "returns": "array: 'Chugiak','Brighton'"
                }
        ]
}