[R] strsplit on comma, with a trailing comma in input

[Peter Dalgaard]

dankelley wrote:
> I have a comma-separated data file in which trailing commas sometimes occur. 
> I am using strsplit to extract the data from this file, and it seems great
> except in cases with trailing comma characters.
>
> The example below illustrates.  What I'd like is to get a fourth element in
> the answer, being an empty string just like the second element.  Is there a
> way I can express my patter (or perhaps specify perl or extended) to get
> that?
>
>
>   
>> strsplit("a,,b,", ",")[[1]]
>>     
> [1] "a" ""  "b"
>   
Hmm, I don't think strsplit can do that. However:

 > scan(textConnection("a,,b,"), sep=",", what="")
Read 4 items
[1] "a" ""  "b" ""

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