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Concatenates Rd objects or pieces





objects to be concatenated, Rd objects or character strings, see `Details'.


The arguments may be a mixture of lists and character strings. The lists are typically "Rd" objects or pieces. The character strings may also be elements of "Rd" objects carrying "Rd_tag" attributes. The "Rd_tag" attribute of character strings for which it is missing is set to "TEXT". Finally, each character element of "\dots" is enclosed in list.

Eventually all arguments become lists and they are concatenated using c(). If any of the arguments is of class "Rd", the class of the result is set to "Rd". Otherwise, the "Rd_tag" of the result is set to the first (if any) non-null "Rd_tag" in the arguments.

The structure of "Rd" objects is described by Murdoch (2010) .


An Rd object or a list whose attribute "Rd_tag" is set as descibed in `Details'


Georgi N. Boshnakov

See also


Duncan Murdoch (2010). “Parsing Rd files.”


a1 <- char2Rdpiece("Dummyname", "name")
a2 <- char2Rdpiece("Dummyallias1", "alias")
a3 <- char2Rdpiece("Dummy title", "title")
a4 <- char2Rdpiece("Dummy description", "description")

## The following are equivalent
## (gbRd::Rdo_empty() creates an empty list of class 'Rd')
b1 <- c_Rd(gbRd::Rdo_empty(), list(a1), list(a2), list(a3), list(a4))
c1 <- c_Rd(gbRd::Rdo_empty(), list(a1, a2, a3, a4))
d1 <- c_Rd(gbRd::Rdo_empty(), list(a1, a2), list(a3, a4))
identical(c1, b1)
identical(c1, d1)

## insert a newline
d1n <- c_Rd(gbRd::Rdo_empty(), list(a1, a2), Rdo_newline(), list(a3, a4))
#> Loading required namespace: gbRd
#> List of 5
#>  $ :List of 1
#>   ..$ : chr "Dummyname"
#>   .. ..- attr(*, "Rd_tag")= chr "VERB"
#>   ..- attr(*, "Rd_tag")= chr "\\name"
#>  $ :List of 1
#>   ..$ : chr "Dummyallias1"
#>   .. ..- attr(*, "Rd_tag")= chr "VERB"
#>   ..- attr(*, "Rd_tag")= chr "\\alias"
#>  $ : chr "\n"
#>   ..- attr(*, "Rd_tag")= chr "TEXT"
#>  $ :List of 1
#>   ..$ : chr "Dummy title"
#>   .. ..- attr(*, "Rd_tag")= chr "TEXT"
#>   ..- attr(*, "Rd_tag")= chr "\\title"
#>  $ :List of 1
#>   ..$ : chr "Dummy description"
#>   .. ..- attr(*, "Rd_tag")= chr "TEXT"
#>   ..- attr(*, "Rd_tag")= chr "\\description"
#>  - attr(*, "class")= chr "Rd"

## When most of the arguments are character strings
## the function 'list_Rd' may be more convenient.
u1 <- list_Rd(name = "Dummyname", alias = "Dummyallias1",
              title = "Dummy title", description = "Dummy description",
              Rd_class = TRUE )