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Export R objects to multiple file types

Source: R/cff_write_misc.R
cff_write_misc.Rd

Export R objects representing citations to specific file formats:

  • cff_write_bib() creates a .bib file.

  • cff_write_citation() creates an R citation file as described in Section 1.9 of Writing R Extensions (R Core Team 2026).

Usage

cff_write_bib(
  x,
  file = tempfile(fileext = ".bib"),
  append = FALSE,
  verbose = TRUE,
  ascii = FALSE,
  ...
)

cff_write_citation(
  x,
  file = tempfile("CITATION_"),
  append = FALSE,
  verbose = TRUE,
  ...
)

Arguments

x

A bibentry or a cff object.

file

Name of the file to be created. If NULL, the lines are displayed instead.

append

A logical value. If TRUE, append entries to an existing file.

verbose

A logical value. If TRUE, display informative messages.

ascii

A logical value. If TRUE, write entries using ASCII characters only.

...

Arguments passed on to as_bibentry.cff, as_bibentry.cff_ref, as_bibentry.cff_ref_lst

what

Fields to extract from a full cff object. It can be:

  • preferred: Create a single entry with the main citation information of the package (key preferred-citation).

  • references: Extract all entries of the references key.

  • all: Extract both the preferred-citation and references keys.

See vignette("r-cff", package = "cffr").

Value

Invisibly returns NULL. This function is called for its side effect of writing a file or displaying its contents.

Details

When x is a cff object, it is converted to BibTeX using toBibtex.cff().

For security reasons, if the file already exists, the function creates a backup copy in the same directory.

References

R Core Team (2026). Writing R Extensions. https://cran.r-project.org/doc/manuals/r-release/R-exts.html.

See also

vignette("bibtex-cff", package = "cffr"), knitr::write_bib() and the following packages:

Work with BibTeX metadata: as_bibentry(), cff_read(), cff_read_bib_text(), encoded_utf_to_latex()

Write citation metadata files: cff_write()

Examples

bib <- bibentry("Misc",
  title = "My title",
  author = "Fran Pérez"
)

my_temp_bib <- tempfile(fileext = ".bib")

cff_write_bib(bib, file = my_temp_bib)
#> ℹ Writing 4 entries.
#> ✔ Results written to /tmp/RtmpwvOiQz/file60473e9d5c6.bib.

cat(readLines(my_temp_bib), sep = "\n")
#> @Misc{,
#>   title = {My title},
#>   author = {Fran Pérez},
#> }

cff_write_bib(bib, file = my_temp_bib, ascii = TRUE, append = TRUE)
#> ℹ Saving a backup of /tmp/RtmpwvOiQz/file60473e9d5c6.bib as /tmp/RtmpwvOiQz/file60473e9d5c6.bib.bk1.
#> ℹ Writing 4 entries.
#> ✔ Results written to /tmp/RtmpwvOiQz/file60473e9d5c6.bib.

cat(readLines(my_temp_bib), sep = "\n")
#> @Misc{,
#>   title = {My title},
#>   author = {Fran Pérez},
#> }
#> @Misc{,
#>   title = {My title},
#>   author = {Fran P{\'e}rez},
#> }
# Create an R citation file.
# Use a system file.
f <- system.file("examples/preferred-citation-book.cff", package = "cffr")
a_cff <- cff_read(f)

out <- file.path(tempdir(), "CITATION")
cff_write_citation(a_cff, file = out)
#> ℹ Writing 1 entry.
#> ✔ Results written to /tmp/RtmpwvOiQz/CITATION.

# Check by reading with a meta object.
meta <- packageDescription("cffr")
meta$Encoding <- "UTF-8"

utils::readCitationFile(out, meta)
#> To cite package ‘cffr’ in publications use:
#> 
#>   Bueler E (2021). _PETSc for Partial Differential Equations: Numerical
#>   Solutions in C and Python_. SIAM Press, Philadelphia. ISBN
#>   978111976304. <https://github.com/bueler/p4pdes>.
#> 
#> A BibTeX entry for LaTeX users is
#> 
#>   @Book{bueler:2021,
#>     title = {PETSc for Partial Differential Equations: Numerical Solutions in C and Python},
#>     author = {Ed Bueler},
#>     year = {2021},
#>     publisher = {SIAM Press},
#>     address = {Philadelphia},
#>     isbn = {978111976304},
#>     url = {https://github.com/bueler/p4pdes},
#>   }