[R] Multiple line commands in R scripting

[Peter Ehlers]

Peter Ehlers wrote:
> As usual, you're Duncan. Should have tested it. Thanks for the correction.

Well, at least I assume that you're still Duncan.
Meant to say, of course: "as usual, you're _right_, Duncan".
Particularly slow fingers today.
Please accept apology.

  -Peter Ehlers

> 
>  -Peter Ehlers
> 
> Duncan Murdoch wrote:
>> On 25/10/2009 11:43 AM, Peter Ehlers wrote:
>>> Here are two ways:
>>>
>>> 1. wrap the line in braces:
>>>
>>>   x <- {....
>>>         /...}
>>
>> That doesn't work.  You're probably thinking of the way the parsing of 
>> if versus if/else depends on braces:
>>
>>  if (TRUE) print("TRUE")
>>  else print("FALSE")
>>
>> is a syntax error, except when wrapped in braces.
>>
>> Duncan Murdoch
>>
>>>
>>> 2. maybe more awkward in general, but sometimes useful:
>>>
>>>   x <- `/`(... ,
>>>         ...)
>>>
>>>   -Peter Ehlers
>>>
>>> Neil Stewart wrote:
>>>> I'm wondering whether there is a character to let R know to expect more
>>>> input for a command on subsequent lines. Here is an example:
>>>>
>>>> test_1.R:
>>>> x <- c(1,2,3,4)
>>>>     / c(1,2,3,4)
>>>> x
>>>>
>>>> R CMD BATCh test_1.R produces test_1.Rout:
>>>>> x <- c(1,2,3,4)
>>>>>   / c(1,2,3,4)
>>>> Error: unexpected '/' in "  /"
>>>> Execution halted
>>>>
>>>>
>>>> test_2.R:
>>>> x <- c(1,2,3,4) /
>>>>     c(1,2,3,4)
>>>> x
>>>>
>>>> R CMD BATCh test_1.R produces test_2.Rout:
>>>>> x <- c(1,2,3,4) /
>>>> +   c(1,2,3,4)
>>>>> x
>>>> [1] 1 1 1 1
>>>>
>>>> test_2.R works as expected but test_1.R fails because the "/" 
>>>> operator is at
>>>> the start of line 2 not the end of line 1.
>>>>
>>>> Is the some kind of continuation charater one can include in a 
>>>> script so R
>>>> is expecting input on the next line? For example, in other 
>>>> languages, "\"
>>>> works. Without this, one is forced to break lines carefully in the 
>>>> middle of
>>>> a function, for example, to ensure R is expecting more. Any comments 
>>>> very
>>>> welcome.
>>>>
>>>> Thank you,
>>>> Neil.
>>>>
>>>> ______________________________________________
>>>> R-help at r-project.org mailing list
>>>> 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.
>>>>
>>>>
>>>
>>> ______________________________________________
>>> R-help at r-project.org mailing list
>>> 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.
>>
>>
> 
> ______________________________________________
> R-help at r-project.org mailing list
> 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.
> 
>