Source §2: list program crashes frontend

[martin-henz]

pair(list(1), 2);

currently crashes sourceacademy.org, see https://share.sourceacademy.org/caxir

Note that the stepper now handles this program correctly. The problem might be type-related; console shows:

96669.eebb44cf.js:2897 Error handled by React Router default ErrorBoundary: TypeError: Cannot read properties of undefined (reading 'type')
    at e (index.d601d906.js:438:6400)
    at index.d601d906.js:438:6925
    at ec (index.d601d906.js:438:7209)
    at ad (lib-react.917565be.js:2:58521)
    at i (lib-react.917565be.js:2:119389)
    at oO (lib-react.917565be.js:2:99066)
    at oF (lib-react.917565be.js:2:98936)
    at oC (lib-react.917565be.js:2:96041)
    at r8 (lib-react.917565be.js:2:44927)
    at lib-react.917565be.js:2:93621

[martin-henz]

Some more observations:

pair(pair(1, 2), 3);

crashes but

pair(1, 2);

works.

Curiously, this also works:

pair(3, pair(1, 2));

[tohlh]

If you build js-slang and run the repl directly, the above cases seem to work fine. Hence, I believe this issue is unlikely to be "type related" in a language implementation sense, but more likely to be related to other components such as the frontend.

[sayomaki]

Issue has been triaged and found to be under frontend side, as evaluating with the stepper tab open works as expected and no errors observed. Moving to frontend.