Reserved keyword "display"

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Harlan Gilbert

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Apr 21, 2022, 8:56:22 AM4/21/22

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Dear Bruce,

There is no action or response particularly needed on this, but I just discovered that display is effectively a reserved keyword, and that redefining this (e.g. making it a user-defined function) does very strange things.

Web VPython 3.2
def display(entry, i):
pass
for n in range(20):
display(1,-1)

Gives

TypeError: right-hand side of 'in' should be an object, got number

Weird!

Very best regards,

Harlan

Bruce Sherwood

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Apr 21, 2022, 8:06:30 PM4/21/22

to Glowscript Users

Sorry about that. Historical VPython called what we now call a "canvas" a "display", so to make it a bit easier to move from old VPython to new we define display = canvas. Whenever we go to Web VPython 3.3 that archaic statement should be removed.

By the way, a reason for changing from display to canvas was that "display" has a crucial role in the Jupyter notebook environment.