Applying condition on variable labels

[Alex Waits]

Dear stata users,
I am curious whether it is possible to apply IF on variable labels.
Or is there any other method, if I want to drop all the variables that have label starting with @
If this topic has been discussed before, please refer me to the relevant forum thread
Many thanks for your advice

[Nick Cox]

. sysuse auto, clear
(1978 Automobile Data)

. gen bad = 42

. label var bad "@unloved, unwanted, throw this out"

. ds, has(varlabel "@*")
bad

. drop `r(varlist)'

. ds
make          mpg           headroom      weight        turn          gear_ratio
price         rep78         trunk         length        displacement  foreign