Hi,

it happens the following, I write for example:

Code:
use "db.dta"
[...]
gen year = start + delta
where `start` and `delta` are defined in `db.dta`.

Then I realize I want to modify `start`.
So for example taking the log.
I then create a new variable and delete the old one, but I may forget to change the usage in later code.
So I end up with:
Code:
use "db.dta"
gen start2 = log(start)
drop start
[...]
* forgot to change here :(
gen year = start + delta
Of course the formula for year is no longer valid.

Other languages (R, Python), would throw an error here: `start` is not defined.

But STATA "expands" the variable name and use `start2` instead of `start`.

How can I deactivate this feature and get an error if the variable is not defined?