On Sun, 7 Nov 2021 09:02:36 +0530 Deepayan Sarkar <deepayan.sar...@gmail.com> wrote:
> This sounds like a difference in precedence. The expression > > if (log) 1 else dnorm(x, mean, sd) / sd > > is apparently being interpreted differently as > > d1: (if (log) 1 else dnorm(x, mean, sd)) / sd > d2: if (log) 1 else (dnorm(x, mean, sd)) / sd) > > It's unclear how environments could affect this, so it would be very > helpful to have a reproducible example. This seems to be caused by the deparser producing the same source text for different expressions: ( x <- expression(`/`(`*`(a, if (b) c else d), e)) ) # expression(a * if (b) c else d/e) ( y <- expression(a * if (b) c else d/e) ) # expression(a * if (b) c else d/e) all.equal(x, y) # [1] TRUE The expressions *seem* to be the same, but: as.list(x[[1]]) # [[1]] # `/` # # [[2]] # a * if (b) c else d # # [[3]] # e as.list(y[[1]]) # [[1]] # `*` # # [[2]] # a # # [[3]] # if (b) c else d/e Perhaps it could be possible to make the deparser output extra parentheses at the cost of slightly uglier output in cases when they are not needed. all.equal.language uses deparse(), so it will behave correctly when the deparse() output is fixed. In the original example, as.list(body(d1)) and as.list(body(d2)) should show different results, too. -- Best regards, Ivan ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
