[catern]

If you have multiple threads which try to bind the dynamically scoped variable to a new value, that should work fine and result in different values for the variable in each thread.

In this implementation, the threads will corrupt the data structure and result in undefined behavior.

[masklinn]

> If you have multiple threads which try to bind the dynamically scoped variable to a new value, that should work fine and result in different values for the variable in each thread.

That would work with proper threadlocals. However with dynamic variables you'd also get this for different sub-thread stacks. Not all languages can expose that but languages with generators do e.g. in Python if you `yield` then the stack is suspended, this means a threadlocal you've changed would not be rolled back, but a dynamic variable (which Python does not have) would.

[jolmg]

Yes, that's why:

> besides the thread issue you mentioned