How much is set in stone?

[Paul Rubin]

Grant Griffin <not.this at seebelow.org> writes:
> Python's system is basically "you must write to a variable before you
> can read it".  This has the net effect of catching the kind of error you
> refer to, in nearly all cases--and I haven't had a significant problem
> with the cases that can get missed.
> 
> Therefore, this simple but powerful idea gives you nearly all of the
> benefit of variable declarations, yet none of the baggage.

Of course it doesn't.  If you misspell a symbol in some rarely used
path through the code, it's quite possible your testing will miss it.
Compile time checking wouldn't.