odd that it's not in already, given that PGraphics is supported (at least the Processing 2.0 API version). Marking as good first bug.

This is the code snippet I was looking at.

background(500);
clear();
rect(50, 60, 70, 100);
size(100, 100);
arc(50, 60, 90, 80, 80, 100);

In the above example, I can try to instantiate a Processing object and catch its error and use it on my page.

try {
    new Processing(canvas, code);
} catch (err) {
    $('#error-message').html(err);
}

Then used in setup and draw as below, an error message is not thrown that I can catch. The error message generated below is logged in the browser console from processing.min.js:896, version 1.6.0. I am not able to catch this one using the same code as above.

void setup() {
    size(200,200,P3D);
}
void draw() {
    clear();
    box(125,125,125);
}