2htdp/image result display in DrRacket exposes internal bitmap.rkt OOM location

[jasonhemann]

Displaying a large 2htdp/image value in DrRacket can expose an internal racket/draw source loc (draw/private/bitmap.rkt:169:2) with out of memory. This differs from behavior in other situations, where such errors are reported as plain out of memory.

I think the result-rendering failure should probably be reported without blaming an internal library location, or with a beginner-facing message such as “image is too large to display under the current memory limit.”

#lang htdp/isl+
(require 2htdp/image)

(define WIDTH 25000000)

(rectangle WIDTH 1 "solid" "blue")
--------------------------------------------
Welcome to DrRacket, version 9.1 [cs].
Language: htdp/isl+, with test coverage [custom]; memory limit: 128 MB.
. . ../../Applications/Racket v9.1/share/pkgs/draw-lib/racket/draw/private/bitmap.rkt:169:2: out of memory
> 

This does also present user the OOM pop-up box, which is expected.

[rfindler]

It looks like the reason this error happens in this way is that it isn't happening during the evaluation of the program, but it is happening while DrRacket is trying to display the image in the interactions window (but apparently still under the memory limit).

(This is not intended to be a solution, just an observation about what's going on here. Still need to think to know what the right response is.)

[jasonhemann]

Ohhh... that makes more sense then, how that behavior is happening.