works in trinket not webvpython

[Michael Burns-Kaurin]

Is there a difference between 2.9 and 3.2 so that code working on trinket.io will give this error on glowscript.org:

SyntaxError: Function statements require a function name

[Michael Burns-Kaurin]

Oh, I get the same error on trinket using 3.1.

[Bruce Sherwood]

Please provide a SHORT program that demonstrates the bug, otherwise there's no way to explore the issue.

Bruce

[Michael Burns-Kaurin]

By gradually adding pieces, I think the culprit is this line:

for ball in (bal for bal in lightBalls if bal.flag):

Oddly, I think I can revise it using the filter function now that it works in 3.2 (but I suppose it won't work in trinket 3.1?).

[Joe Heafner]

On Nov 11, 2021, at 08:32, Michael Burns-Kaurin <burnsk...@gmail.com> wrote:

By gradually adding pieces, I think the culprit is this line:

for ball in (bal for bal in lightBalls if bal.flag):

Oddly, I think I can revise it using the filter function now that it works in 3.2 (but I suppose it won't work in trinket 3.1?).

Trinket lags behind updates because they must manually update their system manually and aren’t always aware of changes. I’ll put a bug in their ear.

Joe Heafner

Sent from my iPhone

[Bruce Sherwood]

You unfortunately don't provide a program that we can test, but it seems possible that the complexity of the statement "for ball in (bal for bal in lightBalls if bal.flag):" means that RapydScript (and/or Web VPython) might not handle this structure correctly in transpiling from Python to JavaScript.

Bruce

[Michael Burns-Kaurin]

That seems likely since I had a similar problem using lambda.  Here is a shortened program that works in 2.9 but fails in 3.1 and 3.2:

lightBalls = []

flag = True

for i in range(6):

    b = sphere(radius = i+1)

    b.flag = flag

    flag = not flag

    b.num = i

    print(i,b.flag,b.num)

    lightBalls.append(b)

for ball in (bal for bal in lightBalls if bal.flag):

    print(ball.num)

[Bruce Sherwood]

Your program now works correctly in Web VPython 3.2. Thanks for the clear report.

Bruce

[Michael Burns-Kaurin]

Thanks for your diligent hard work.  I guess not many have tried some of these python things in glowscript before.

[Bruce Sherwood]

Yes, recently there have been quite a few sophisticated users of VPython reporting bugs that have been present and unreported for years.

Bruce