[Bioc-devel] Convertion of DataFrame with XStringSets to data.frame

[Julian Gehring]

Hi,

With the latest bioc-devel, the convertion of XStringSets within a 
DataFrame to a data.frame behaves strangely:

   library(Biostrings)
   dss = DNAStringSet(c("ACT", "AAA"))
   DF = DataFrame(dss)

   as(DF, "data.frame")

In the latest bioc-devel, this splits the strings:

   dss.group dss.group_name dss.value
1         1           <NA>         A
2         1           <NA>         C
3         1           <NA>         T
4         2           <NA>         A
5         2           <NA>         A
6         2           <NA>         A

In older versions of bioc-devel (e.g. from last week) and bioc-stable, 
this keeps the structure and converts to strings to factor levels:

   dss
1 ACT
2 AAA

Any idea what is causing this?

Best wishes
Julian