## From: Peter Bosa <Peter.Bosa@oregonmetro.gov>
## To: "R-devel@r-project.org" <R-devel@r-project.org>
## Subject: [Rd] Possible repeat{} / break function bug in R 3.4.1
## Date: Tue, 22 Aug 2017 14:39:50 +0000

## Hello, I've noticed the following error using repeat{} / break in R 3.4.1 running on Windows 10 and Windows Server 2008 (both 64-bit environments).

## When running a repeat function, the break command causes an error message if the repeat command refers to code within a file, but does not produce an error if the code is contained within the repeat{} command.

## For example, the following code runs fine:

x <- 1
y <- 5
repeat {
  if(x < y) {
    writeLines("No Break Dance :-(")
    x <- x + 1
  } else {
    writeLines("Break Dance!")
    break
  }
}
## No Break Dance :(
## No Break Dance :(
## No Break Dance :(
## No Break Dance :(
## No Break Dance :(
## Break Dance!
## >

## However, if I take the loop contents of the repeat{} function, and save
## them to a file (breakTest.R) that contains the following:
##                 ^^^^^^^^^^^
##                __SEE THAT FILE__
## if(x < y) {
##   writeLines("No Break Dance :-(")
##   x = x + 1
## } else {
##   writeLines("Break Dance!")
##   break
## }

## And then run the following code:

x <- 1
y <- 5
repeat{
  source("./breakTest.R")
}
cat("successfully finished\n")

## I get the following error:

## No Break Dance :(
## No Break Dance :(
## No Break Dance :(
## No Break Dance :(
## No Break Dance :(
## Break Dance!
## Error in eval(ei, envir) : no loop for break/next, jumping to top level
## ^^^^^^^^^^^^^^^^^^^^


## This was not an issue with previous versions of R that I have used, including 3.3.3.

## MM: It does work in R 3.3.3, indeed
## --  it fails in R 3.4.0 and later


## Any suggestions? Is this a known bug with 3.4.1?

## Cheers-
## Peter


## ----------------------------------------------------------------
## peter bosa
## metro
## modeling services
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## portland, or  97232

## peter.bosa@oregonmetro.gov<mailto:peter.bosa@oregonmetro.gov>
## 503.797.1771

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