expressions render in user-facing syntax

[bob-carpenter]

There are still some cases that aren't working properly.

• indexing

[VMatthijs]

Could you clarify this issue a bit more?

[bob-carpenter]

We got better at this but right no we can have errors in "a * b" that get translated as "multiply(a, b)" in the error messages, even though the user never wrote "multiply". This is an issue with any kind of intermediate form normalization (* being replaced with multiply here)---we need a path back to the actual user input.

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On Dec 13, 2018, at 8:18 AM, Matthijs Vákár ***@***.***> wrote: Could you clarify this issue a bit more? — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub, or mute the thread.

[VMatthijs]

Ah right. This has been fixed in stanc3, then. It comes with a pretty printer to render an AST as Stan syntax. (Can be used for auto-formatting.) The error messages thrown by the compiler render AST nodes using this pretty printer whenever they need to refer to a node in the error. In particular, operators get rendered properly.

[rok-cesnovar]

Fixed in stanc3 as Matthijs mentioned above.