Which getindex expression threw BoundsError

[nsajko]

@mnemnion

The workaround while debugging is to put each part of the expression on its own line, something like this:

Yes, but

@mnemnion

let n = 2, m = 3
           xs = randn(n)
           ys = randn(m)
           (xs[m] + 
            ys[n])
       end
end

This isn’t enough. Assigning xs[m] and ys[n] to variables is. The problem is that, after some compilation stage, Julia doesn’t know that the expression has more than one line. I guess that lowering is to blame here, according to Sukera?

I wonder how relevant this message still is (since then we got JuliaSyntax.jl and LLVM could have gotten some relevant improvements, too?):

Make Julia’s Error Codes Even Better Than Elm’s

At a higher level, since it may not be clear to people, Julia is in a tricky spot when it comes to error messages. Static languages like Elm have a relatively slow compilation phase which doesn’t affect runtime. Note that the linked page is about compiler errors. The example given here is a runtime error—out of bounds index. (Genuine question: how are Elm’s runtime errors? Does it tell you what invalid index you used?) When an error occurs during compilation, if compilation is a separate step yo…

Somewhat related issues on Github:

Better parsing errors: indicate position with a caret

Type error within struct reported without actual error line

New issue:

finer-grained location info for error messages, strack traces: line number, column number