panic when creating a list using bool or NA values

[APILLSBURY]

When sending a command to create a list I'm getting a panic: runtime error: index out of range with certain combinations of values. What I've observed is the following.

1. Creating a list of strings, ints, and floats in any combination works.
   Ex: list(int=1,string='s',float=0.5)

2. If the list has a bool or NA as the last value, the correct result is returned but there is a Warning: Error whilst constructing vector: Abruptly reached end of buffer outputted.
   Ex: list(int=1,string='s',float=0.5,bool=TRUE)
   Ex: list(var=NA)

3. If the list contains a bool or NA value with anything else following it, a panic happens.
   Ex: list(int=1,string='s',float=0.5,bool=TRUE,anything='this causes a panic')
   Ex: list(var1=NA,var2=1)

Here is the full stack trace for the panic:

panic: runtime error: index out of range

goroutine 1 [running]:
roger/sexp.getLength(0xc820431484, 0x38, 0x38, 0x29, 0x1, 0x420460, 0x0, 0x0)
    roger/sexp/factory.go:25 +0x12f
roger/sexp.parseReturningOffset(0xc820431484, 0x38, 0x38, 0x29, 0x0, 0x0, 0x0, 0x0, 0x0)
    roger/sexp/factory.go:35 +0xa0
roger/sexp.parseVector(0x437840, 0xc820436960, 0xc820431484, 0x38, 0x38, 0x29, 0x38, 0x0, 0x0, 0x0, ...)
    roger/sexp/xt-vector.go:37 +0xba
roger/sexp.parseReturningOffset(0xc820431484, 0x38, 0x38, 0x20, 0x0, 0x0, 0x8591d, 0x0, 0x0)
    roger/sexp/factory.go:80 +0x752
roger/sexp.Parse(0xc820431484, 0x38, 0x38, 0x0, 0x0, 0x0, 0x0, 0x0)
    roger/sexp/factory.go:13 +0x61
roger.(*packet).GetResultObject(0xc820436930, 0x0, 0x0, 0x0, 0x0)
    roger/packet.go:77 +0x31e

[dareid]

Thanks for the detailed issue!
I will try to look into this issue this weekend. I fear the list parsing is not correct and this probably relates to #24.

[APILLSBURY]

Thanks. Let me know if you need any more info from me.

[harryrose]

Incorrectly closed by my previous commit. Reopening, as NA handling still needs work.

[andrei-m]

Any word on NA? I am interested in using it, but running into this issue.

[dareid]

I have began working on support for NAs in lists, however it is tricky to do in a backwards compatible manner. Hopefully I will get time to finish it off shortly.
I am very open to pull requests for this