adply unexpected behavior when row raises an exception

[jeffwong]

Hello, I am looping over rows of a data frame and doing some computation. Sometimes that computation throws an error for a specific row. I wrap everything in a tryCatch where adply correctly returns the value inside my error handler.

grid = data.frame(a = 1:3, b = 1:3)

xxx = adply(grid, 1, function(i) {
tryCatch({
if(any(i == 3)) {
stop("bad value")
} else {
return (4)
}
}, error = function(e) {
test = 2+3
return (test)
})
}, .inform=T)

Correctly returns xxx is
a b V1
1 1 1 4
2 2 2 4
3 3 3 5

Now if my error handler also prints a message about the error, e, adply fails.

grid = data.frame(a = 1:3, b = 1:3)

xxx = adply(grid, 1, function(i) {
tryCatch({
if(any(i == 3)) {
stop("bad value")
} else {
return (4)
}
}, error = function(e) {
message(e)
test = 2+3
return (test)
})
}, .inform=T)

Error in try(.fun(piece, ...)) : bad value
Error: with piece 3:
a b
3 3 3

xxx
Error: object 'xxx' not found

The pain point is that downstream I am expecting the variable xxx to exist, whether it's V1 column is populated with values from Catch or it is populated from values with Try. If I have message(e) in the error handler the variable xxx never gets set

[ankur-gupta]

I think message(e) throws an error.

grid = data.frame(a = 1:3, b = 1:3)

xxx = adply(grid, 1, function(i) {
  tryCatch({
    if(any(i == 3)) {
      stop("bad value")
    } else {
      return (4)
    }
  }, error = function(e) {
    message(e)
    print("This is never executed")
    test = 2+3
    return (test)
  })
}, .inform=T)

Try using print(e) instead.