I wrote,
> Abbreviations can hurt you even if you don't ever use them,
> such as
>
> i) dropping a variable you never intended to drop; or
>
> ii) inadvertently modifying the wrong variable
>
> For e.g., at some point in time your data contains
> variables _foo_ and _foobar_. You no longer need _foo_
> so you -drop- it. Later, (wrongly) believing _foo_ is
> still defined, you -replace foo = ...- but it modifies
> -foobar- instead since Stata finds no ambiguity in the
> string literal _foo_. You might never notice this blunder.
> Dealing with large datasets at times, with hundred of
> variables possessing names that differ by only a character
> or two, this can have unfortunate consequences. I almost
> never use abbreviations myself either and typically, when
> I want to modify _foo_, it is _foo_ I want to change and
> certainly *not* _foobar_.
to which Nick replied,
> As mentioned in an earlier posting, safe dropping is
> entirely controllable. The question came up on the list a few years
> ago and I posted some code, although my guess was then
> -- perhaps wrongly -- that it was a one-off request.
>
>(code omitted, see Nick's earlier email)
Very true, and a similar routine can be used to handle safe replacing, i.e.
cap prog drop safereplace
program def safereplace
*! in the spirit of safedrop.ado by N.J.Cox
*! version 1.0 12fev2003 PJoly
version 7.0
unab V : `1'
if "`V'" != "`1'" {
di as err "`1' incomplete variable name"
exit 198
}
replace `0'
end
That said, these wrapper routines are not really the answer since any other
.ado command (whether user-written or official Stata) that drops or replaces
variables does so using -drop- and not -safedrop-. Like Lee, I wouldn't go
as far as picketing in front of Stata headquarters but perhaps I could say
that a pragmatic module to toggle abbreviations on or off would probably
help me sleep better at night. :)
Patrick Joly
[email protected]
[email protected]
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