Compile rules against a Sass Bundle or Sass Layer object

Replaces the rules for a sass_layer() object with new rules, and compile it. This is useful when (for example) you want to compile a set of rules using variables derived from a theme, but you do not want the resulting CSS for the entire theme -- just the CSS for the specific rules passed in.

sass_partial(
  rules,
  bundle,
  options = sass_options_get(),
  output = NULL,
  write_attachments = NA,
  cache = sass_cache_get(),
  cache_key_extra = NULL
)

Arguments

rules: A set of sass rules, which will be used instead of the rules from layer.
bundle: A sass_bundle() or sass_layer() object.
options: Compiler sass_options().
output: Specifies path to output file for compiled CSS. May be a character string or output_template()
write_attachments: If the input contains sass_layer() objects that have file attachments, and output is not NULL, then copy the file attachments to the directory of output. (Defaults to NA, which merely emits a warning if file attachments are present, but does not write them to disk; the side-effect of writing extra files is subtle and potentially destructive, as files may be overwritten.)
cache: This can be a directory to use for the cache, a FileCache object created by sass_file_cache(), or FALSE or NULL for no caching.
cache_key_extra: additional information to considering when computing the cache key. This should include any information that could possibly influence the resulting CSS that isn't already captured by input. For example, if input contains something like "@import sass_file.scss" you may want to include the file.mtime() of sass_file.scss (or, perhaps, a packageVersion() if sass_file.scss is bundled with an R package).

Examples

theme <- sass_layer(
  defaults = sass_file(system.file("examples/variables.scss", package = "sass")),
  rules = sass_file(system.file("examples/rules.scss", package = "sass"))
)

# Compile the theme
sass(theme)
#> /* CSS */
#> body {
#>   background-color: #333;
#>   color: white;
#>   font-size: 16px;
#> }
#> 

# Sometimes we want to use the variables from the theme to compile other sass
my_rules <- ".someclass { background-color: $bg; color: $fg; }"
sass_partial(my_rules, theme)
#> /* CSS */
#> .someclass {
#>   background-color: #333;
#>   color: white;
#> }
#>