programming languages - What does it mean by saying conflating environment and object is the fundamental sin of Javascript? -


i watching programming languages courses given prof. shriram krishnamurthi on youtube.

in episode, https://youtu.be/suh7jhrtktk?t=1600

he said conflating environment , objects fundamental sin of javascript. environment exposed language users, , users can manipulate environment.

i don't quite understand means actually. refer how "this" works in javascript?

are there code examples can demonstrate sin?

after little bit of digging, i’ve found paper professor shriram’s group.

https://cs.brown.edu/research/plt/dl/jssem/v1/

in section 2.5, pointed out not clear whether javascript lexically scoped because scope chain in javascript formed ordinary objects, , with statement lets programmers add arbitrary objects scope chain.

i think understand means in video.

i highly recommend paper. indeed catches of essence of javascript according title, not part, bad part.


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