4.8.1. Type Hint: JavaScript Code

You can specify type hints to a writer via type_hints.

Sample Code:

Using type hint to change the data type to write JavaScript code

from datetime import datetime
from pytablewriter import JavaScriptTableWriter

def main():
    writer = JavaScriptTableWriter()
    writer.headers = ["header_a", "header_b", "header_c"]
    writer.value_matrix = [
        [-1.1, "2017-01-02 03:04:05", datetime(2017, 1, 2, 3, 4, 5)],
        [0.12, "2017-02-03 04:05:06", datetime(2017, 2, 3, 4, 5, 6)],
    ]

    print("// without type hints: column data types are detected automatically by default")
    writer.table_name = "without type hint"
    writer.write_table()

    print("// with type hints: values will be converted with type hints if possible")
    writer.table_name = "with type hint"
    writer.type_hints = ["int", "datetime", "str"]
    writer.write_table()

if __name__ == "__main__":
    main()

Output:

JavaScript variable declaration code with/without type hints

// without type hints: column data types are detected automatically by default
const without_type_hint = [
    ["header_a", "header_b", "header_c"],
    [-1.1, "2017-01-02 03:04:05", new Date("2017-01-02T03:04:05")],
    [0.12, "2017-02-03 04:05:06", new Date("2017-02-03T04:05:06")]
];

// with type hints: values will be converted with type hints if possible
const with_type_hint = [
    ["header_a", "header_b", "header_c"],
    [-1, new Date("2017-01-02T03:04:05"), "2017-01-02 03:04:05"],
    [0, new Date("2017-02-03T04:05:06"), "2017-02-03 04:05:06"]
];