39 lines
540 B
Markdown
39 lines
540 B
Markdown
The solution is to return the object itself from every call.
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```js run demo
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let ladder = {
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step: 0,
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up() {
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this.step++;
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*!*
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return this;
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*/!*
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},
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down() {
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this.step--;
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*!*
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return this;
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*/!*
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},
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showStep() {
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alert( this.step );
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*!*
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return this;
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*/!*
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}
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};
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ladder.up().up().down().showStep().down().showStep(); // shows 1 then 0
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```
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We also can write a single call per line. For long chains it's more readable:
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```js
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ladder
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.up()
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.up()
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.down()
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.showStep() // 1
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.down()
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.showStep(); // 0
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```
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