2.8 KiB
option-chain
Use fluent property chains in lieu of options objects.
Install
$ npm install --save option-chain
Usage
const optionChain = require('option-chain');
const optionDefinition = {
defaults: {
bar: false
},
chainableMethods: {
foo: {foo: true},
notFoo: {foo: false},
bar: {bar: true}
}
};
function printOptionsAndArgs(options, args) {
console.log(options);
if (args.length) {
console.log(args);
}
}
const fn = optionChain(optionDefinition, printOptionsAndArgs);
fn();
//=> [{bar: false}]
fn.bar();
//=> [{bar: true}]
fn.foo.bar();
//=> [{foo: true, bar: false}]
fn.foo('a', 'b');
//=> [{foo: true, bar: false}]
//=> ['a', 'b']
API
optionChain(options, callback, [target])
options
chainableMethods
Type: Object
Required
A map of chainable property names to the options set by adding property to the chain.
Given the following:
const chainableMethods = {
foo: {foo: true},
notFoo: {foo: false},
bar: {bar: true},
both: {foo: true, bar: true}
}
Then:
fn.foo
would setfoo
totrue
.fn.bar
would setbar
totrue
.fn.both
sets bothfoo
andbar
totrue
.- The last property in the chain takes precedence, so
fn.foo.notFoo
would result infoo
beingfalse
.
defaults
Type: Object
Default: {}
A set of default starting properties.
spread
Type: boolean
Default: false
By default, any arguments passed to the wrapper are passed as an array to the second argument of the wrapped function. When this is true
, additional arguments will be spread out as additional arguments:
function withoutSpread(opts, args) {
let foo = args[0];
let bar = args[1];
// ...
}
function withSpread(opts, foo, bar) {
// ...
}
callback
Type: function
This callback is called with the accumulated options as the first argument. Depending on the value of options.spread
, arguments passed to the wrapper will either be an array as the second argument or spread out as the 2nd, 3rd, 4th... arguments.
target
If supplied, the target
object is extended with the property getters and returned. Otherwise a wrapper function is created for options.defaults
, then that wrapper is extended and returned.
Hint: If you want to extend a target
and add a method that simply uses the defaults, add a chainable method definition with an empty spec:
const chainableMethods = {
defaultMethodName: {}
}
License
MIT © James Talmage