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19 lines
563 B
Markdown
19 lines
563 B
Markdown
# The Comma Operator
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I was surprised to see the result of this line of code:
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```javascript
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const what = (1,2,3,4);
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console.log(what); //=> 4
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```
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I asked around on
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[twitter](https://twitter.com/jbrancha/status/1084936559323951105) and
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learned that the syntax construct at play here is the [comma
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operator](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Comma_Operator).
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> The comma operator evaluates each of its operands (from left to right) and
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> returns the value of the last operand.
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And that is why `what` gets bound to `4`.
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