Brms package for survival

Hello everyone!
I was trying to use the brm() function from brms() package to fit a survival regression model.
However, even when I use the example given in vignette

fit3 <- brm(time | cens(censored) ~ age * sex + disease + (1|patient),
data = kidney, family = lognormal())

The program gives an error
Error in FUN(X[[i]], …) : could not find function "isFALSE"

Could anyone tell me how to deal with it? Or it is a bug of a package?

Thanks in advance!

This works for me. Make sure you have the latest brms. If for whatever reason you need to define the isFALSE function in your global environment to get it to work, it is just

isFALSE <-
function (x) 
{
    identical(FALSE, x)
}

Thank you!

It is a problem with your R version. After installing R 3.5.0 it should be working correctly. I am about to submit a new brms version to CRAN that fixes this problem for older R versions.

Oh ok, mine is 3.3.2 version, I did not update it yet!

Thanks for explanation