Convert an Rd object to Rd file format

Converts an Rd object to Rd format and saves it to a file or returns it as a character vector. It escapes percents where necessary and (optionally) backslashes in the examples section.

Usage

Rdo2Rdf(rdo, deparse = FALSE, ex_restore = FALSE, file = NULL,
        rcode = TRUE, srcfile = NULL)

Arguments

rdo

an Rd object or a character vector, see `Details'.

deparse

logical, passed to the print method for Rd objects, see `Details'.

ex_restore

logical, if TRUE escapes backslashes where necessary.

file

a filename where to store the result. If NULL or "missing", the result is returned as a character vector.

rcode

if TRUE, duplicate backslahes in RCODE elements, see Details.

srcfile

NULL or a file name, see 'Details'.

Details

The description here is rather technical and incomplete. In any case it concerns almost exclusively Rd files which use escape sequences containing multiple consecutive backslashes or escaped curly braces (such things appear in regular expressions, for example).

In principle, this function should be redundant, since the print and as.character methods for objects of class "Rd" would be expected to do the job. I was not able to get the desired result that way (the deparse option to print did not work completely for me either).

Arguments ex_restore and rcode were added on an ad-hoc basis. rcode is more recent and causes Rdo2Rdf to duplicate backslashes found in any element Rd_tag-ed with "RCODE". ex_restore does the same but only for the examples section. In effect, if rcode is TRUE, ex_restore is ignored.

The initial intent of this function (and the package Rdpack as a whole was not to refer to the Rd source file. However, there is some flexibility in the Rd syntax that does not allow the source file to be restored identically from the parsed object. This concerns mainly backslahes (and to some extent curly braces) which in certain contexts may or may not be escaped and the parsed object is the same. Although this does not affect functionality, it may be annoying if the escapes in sections not examined by reprompt were changed.

If srcfile is the name of a file, the file is parsed and the Rd text of sections of rdo that are identical to sections from srcfile is taken directly from srcfile, ensuring that they will be identical to the original.

Value

NULL, if file is not NULL. Otherwise the Rd formatted text as a character vector.

Author

Georgi N. Boshnakov

Note

Here is an example when the author's Rd source cannot be restored exactly from the parsed object.

In the Rd source "author" has two backslashes here: \author.

In the Rd source "author" has one backslash here: \author.

Both sentences are correct and the parsed file contains only one backslash in both cases. If reprompt looks only at the parsed object it will export one backslash in both cases. So, further reprompt()-ing will not change them again. This is if reprompt is called with sec_copy = FALSE. With the default sec_copy = TRUE, reprompt calls Rdo2Rdf with argument srcfile set to the name of the Rd file and since reprompt does not modify section "Note", its text is copied from the file and the author's original preserved.

However, the arguments of \eqn are parse_Rd-ed differently (or so it seems) even though they are also in verbatim.

Examples

# # this keeps the backslashes in "author" (see Note above)
# reprompt(infile="./man/Rdo2Rdf.Rd")

# # this outputs "author" preceded by one backslash only.
# reprompt(infile="./man/Rdo2Rdf.Rd", sec_copy = FALSE)