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Adopt `options` object for optional parameters

See original GitHub issue

Formalizing @DenisCarriere’s elegant proposal, which I really like. 😄 I would actually include all the optional parameters in the options object, making it more consistent throughout the library.

/**
 * @param {Object} [options={}] Optional parameters
 * @param {string} [options.units="kilometers"] can be degrees, radians, miles, kilometers, ...
 * @param {number} [options.steps=64] number of steps on a rounded corner
 */
module.exports = function (feature, distance, options) {
    options = options || {};
    var units = options.units;
    var steps = options.steps;

As suggested, we might formally adopt this for new modules and refactor the existing modules in the new major release.

cc: @rowanwins

Single optional parameter (Backwards compatible with v4.0)

/**
 * @param {Feature<LineString>} line input line
 * @param {number} distance distance along the line
 * @param {Object} [options] Optional parameters
 * @param {string} [options.units="kilometers"] can be degrees, radians, miles, or kilometers
 */
export default function (line, distance, options) {
    // Backwards compatible with v4.0
    var units = (typeof options === 'object') ? options.units : options;

index.d.ts

interface Options {
    units?: Units;
}
export default function along(line: LineString, distance: number, options?: Options): Point;

Multiple optional parameters (❗️ breaking change)

/**
 * @param {Feature<LineString>} line input LineString
 * @param {Object} [options] Optional parameters
 * @param {number} [options.resolution=10000] time in milliseconds between points
 * @param {number} [options.sharpness=0.85] a measure of how curvy the path should be between splines
*/
export default function (line, options) {
    // Optional params
    options = options || {};
    var resolution = options.resolution || 10000;
    var sharpness = options.sharpness || 0.85;

    // validation
    if (typeof options !== 'object') throw new Error('options must be an object');
    if (typeof resolution !== 'number') throw new Error('options must be an number');
    if (typeof sharpness !== 'number') throw new Error('sharpness must be an number');

index.d.ts

interface Options {
    resolution?: number;
    sharpness?: number;
}
export default function bezier(line: LineString, options?: Options): LineString;

Apply to the following modules:

Issue Analytics

State:
Created 6 years ago
Comments:5 (4 by maintainers)

Top GitHub Comments

1reaction

DenisCarrierecommented, Oct 4, 2017

Done

0reactions

DenisCarrierecommented, Oct 4, 2017

🎉 All done… now just need to review the remaining errors that were caused by the refactoring.

https://github.com/Turfjs/turf/pull/993

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