RStudioThemeTemplate

This is a SASS template for making custom RStudio themes, including editor syntax highlighting. It has the most complete support for syntax highlighting that I've yet seen.

To actually use the theme template, click the big Use this Template button at the top-right of this pane and make your own copy of it.

Install SASS and compile the .sass file to a .rstheme file with

sass --watch "Template_Dark.sass" "C:\Program Files\RStudio\resources\app\resources\themes\Template_Dark.rstheme"

And set it as your theme in RStudio. To reflect any new changes, right-click in RStudio and select Reload.

PS. You can quickly clear out the preset colours by doing a regex find replace: #.{6} → inherit.

Features

• Only has style selectors that actually do something, gleaned from long and painful element inspection in RStudio
• Properly separates syntax highlighting from Markdown highlighting/styles
• Exposes rainbow brackets and rainbow indent guides

Limitations of RStudio/ACE editor

• You can't have text elements of different sizes; it makes the visual cursor no longer point to where the cursor actually is.
• Same for editing the padding and margins of elements too much, it makes the cursor misaligned with the real cursor position.
• Basically all items are spans and display inline. Many elements can be made to display: block, but it can have unintended effects. For example, styling the first and last line of code chunks as display: block means that you can have code blocks that are fully surrounded by a border or book-ended with a different colour background, but it also means that these items will fold into three separate lines instead of folding down to one line.
• The Terminal pane is a bit of a bother. The styles dedicated to its colours take up 500+ lines, so they're in a separate file that gets @imported. I haven't exposed any of the terminal's colours as variables because it was way too easy to accidentally make it unusable.

Theme preview

These colours weren't chosen to be pleasing, they were chosen to show that nearly everything can be styled in this template.

Variable dictionary (things you can edit out-of-the-box)

If anything isn't already here, just add it yourself.

Variable name	User interface	R syntax	Rmarkdown elements	Notes
$base_text_clr			Regular text
$whitespace_clr		Whitespace, if 'Show whitespace characters' is enabled.		Spaces and EOLs can be separately styled, but I did not include that in this template.
$cursor_clr	Text cursor
$editor_bg	Background of all panes			Editable panes (Editor, Console, Render) and non-editable panes (all others) can be styled separately.
$activeline_bg	Active line highlight, if enabled.
$activeline_bdr	Active line highlight, if enabled.
$debugline_bg	Active line in debugger
$codechunk_bg			Rmarkdown code chunks	First and last line of code chunks can be styled separately.
$codechunk_bdr			Rmarkdown code chunks
$codechunk_clr			Rmarkdown code chunks
$fold_clr	Folded block indicator
$gutter_bg	Gutter background
$gutter_clr	Line number colour
$active_selection_bg	Active selection
$active_selection_bdr	Active selection
$inactive_selection_bg	Inactive selection (e.g. matching words)
$inactive_selection_bdr	Inactive selection (e.g. matching words)
$ruler_bdr	Line length ruler
$matching_bdr		Matching bracket
$invalid_clr		Undisplayable characters (e.g. Unicode chars in ASCII file)
$invalid_bg		Undisplayable characters (e.g. Unicode chars in ASCII file)
$comment_clr		Comments and Roxygen blocks
$comment_bg		Comments and Roxygen blocks
$keyword_clr		if, else, stop, etc.
$function_clr		Function names, if 'Highlight R function calls' enabled
$package_clr		Package names to the left of ::
$operator_clr		<- = > etc.
$infix_clr		%in% %>% etc.
$comma_clr		Commas can be specifically styled, for some reason.
$constant_clr		TRUE, FALSE, NA, NULL
$numeric_clr		Integers and Numeric
$string_clr		Strings
$var_arg_clr		Variable names and argument names		Sadly, variable names and argument names cannot be styled separately.
$yamlkey_clr			YAML keys e.g. title:
$code_clr			Backticked and indented code blocks
$bold_clr			Bold text
$italic_clr			Italicised text
$heading_clr			Headings of all levels
$heading_bg			Headings of all levels
$url_clr			Web addresses
$blockquote_clr			Blockquotes
$help_link_clr	In Help pane, colour of link text.
$help_link_bg	In Help pane, background of link text.
$indent_guide_bdr	"Grey lines" style indent guide
$rainbow0	Rainbow indent	Rainbow brackets		Rainbow indent styles (lines vs fill) and rainbow brackets can all be styled separately.
$rainbow1	Rainbow indent	Rainbow brackets
$rainbow2	Rainbow indent	Rainbow brackets
$rainbow3	Rainbow indent	Rainbow brackets
$rainbow4	Rainbow indent	Rainbow brackets
$rainbow5	Rainbow indent	Rainbow brackets
$rainbow6	Rainbow indent	Rainbow brackets

Licensing

This is under the Unlicense and dedicated to the public domain. It would be nice if you gave this project credit if you used it so that others could use it too.