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The Rouge syntax highlighter supports the following keys of the option
‘syntax_highlighter_opts’:
default_lang The default language that should be used when no language
is set. guess_lang If no specific language or a default language is
set, guess the language. formatter A custom Rouge formatter class that
should be used instead of the following default formatter (Rogue 1.x:
Rouge::Formatters::HTML / Rogue 2.x: Rouge::Formatters::HTMLLegacy).
If this setting is a string, it needs to contain the name of a
constant under the Rouge::Formatters namespace.
Note: The formatter class needs to respond to ::new(opts), where opts
is a hash of options, and to #format which needs to return the HTML
formatted source code.
disable If set to true, highlighting with Rouge will be disabled.
Should probably not be set globally but inside the ‘span’ or ‘block’
options.
span A key-value map of options that are only used when syntax
highlighting code spans. block A key-value map of options that are
only used when syntax highlighting code blocks. Furthermore all Rouge
options (e.g. ‘line_numbers’) can be set directly on the
‘syntax_highlighter_opts’ option (where they apply to code spans and
code blocks) and/or on the ‘span’/’block’ keys.