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0 pointssethops125d ago0 comments

When you see .unwrap in Rust code, you know it smells bad. When you see x, _ := in Go code, you know it smells bad.

> But if you don't know Go, it's just an underscore.

And if you don't know rust, .unwrap is just a getter method.

0 comments

n_u25d ago

One big difference is that with unwrap in Rust, if there is an error, your program will panic. Whereas in Go if you use the data without checking the err, your program will miss the error and will use garbage data. Fail fast vs fail silently.

But I'm just explaining the argument as I understand it to the commenter who asked. I'm not saying it is right. They have tradeoffs and perhaps you prefer Go's tradeoffs.

xigoi25d ago

> When you see x, _ := in Go code, you know it smells bad.

What if it’s a function that returns the coordinates of a vector and you don’t care about the y coordinate?

yndoendo24d ago

Haven't jumped into rust for a while. Had to read up on what .unwrap() does.

   x, _ :=

With the topic of .unwrap() _ is referencing an ignored error. Better laid out as:

  func ParseStringToBase10i32AndIDoNotCare(s string) {
     i, _ := strconv.ParseInt(s, 10, 32)
     return i
  }

Un-handled errors in Go keeps the application going were rust crashes .unwrap().

Ignoring an output data value or set is just fine. Don't always need the key and value of a map. Nor a y axes in vector<x,y,z> math.

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