Problem with arrow function with Bangle.js

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•

Robin
Wed 2020.02.05

I've not seen this syntax used with arrow functions: = _=>
```
Test.prototype.draw = _=> {
```
Finally found what might be a suggestion to an answer:

https://stackoverflow.com/questions/41085189/using-underscore-variable-with-arrow-functions-in-es6-typescript/41086381

Anyone able to shed some light within Espruino, and generally with Javascript usage? Thanks

•

AkosLukacs in reply to @Robin

It's just a function parameter :)
The _ is just the single input parameter. You can omit the parens, if there is only a single parameter. But you can think about it as wut = _unusedParameter => 42
Btw boo = () => 42 is the same.

To add more obscurity to it, you can do something like foo = _ => 42 without the curly braces.
Which again is just the equivalent of function˙foo(){ return 42 } :) The 42 after the arrow is an implicit return, if your lambda doesn't have the curly braces { }

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