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write-this

Write into or over a file

Description

Helpers to write into or over a new or pre-existing file. Designed mostly for for internal use. File is written with UTF-8 encoding.

Usage

write_union(path, lines, quiet = FALSE)

write_over(path, lines, quiet = FALSE)

Arguments

`path`	Path to target file. It is created if it does not exist, but the parent directory must exist.
`lines`	Character vector of lines. For `write_union()`, these are lines to add to the target file, if not already present. For `write_over()`, these are the exact lines desired in the target file.
`quiet`	Logical. Whether to message about what is happening.
`contents`	Character vector of lines.

Value

Logical indicating whether a write occurred, invisibly.

Functions

write_union: writes lines to a file, taking the union of what's already there, if anything, and some new lines. Note, there is no explicit promise about the line order. Designed to modify simple config files like .Rbuildignore and .gitignore.
write_over: writes a file with specific lines, creating it if necessary or overwriting existing, if proposed contents are not identical and user is available to give permission.

Examples

write_union("a_file", letters[1:3])
readLines("a_file")
write_union("a_file", letters[1:5])
readLines("a_file")

write_over("another_file", letters[1:3])
readLines("another_file")
write_over("another_file", letters[1:3])
## Not run: 
## will error if user isn't present to approve the overwrite
write_over("another_file", letters[3:1])

## End(Not run)

## clean up
file.remove("a_file", "another_file")

usethis

Automate Package and Project Setup

v2.0.1

MIT + file LICENSE

Authors

Hadley Wickham [aut] (<https://orcid.org/0000-0003-4757-117X>), Jennifer Bryan [aut, cre] (<https://orcid.org/0000-0002-6983-2759>), RStudio [cph, fnd]

Initial release