/usr/share/source-highlight/scheme.lang is in libsource-highlight-common 3.1.8-1.1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 | comment delim "#\|" "\|#" multiline nested
comment start ";"
environment string delim "\"" "\"" begin
specialchar = '\\.'
end
type = '#t|#f|#\\[[:alnum:]]+' nonsensitive
vardef words = '(define|define-syntax|syntax-case|syntax-rules|lambda|let|let\*|letrec|let-syntax|letrec-syntax|if|else|cond|case|and|not|or|begin|for-each|map|delay|do|dynamic-wind|call/cc|call-with-current-continuation|call-with-input-file|call-with-output-file)'
# Match keywords as long as they aren't just a prefix of an identifier
keyword = $words + '(?![[:alnum:]!$%&*+./:<=>?@^_~-])'
# Make any identifier that doen't start with a keyword be normal
normal = '(?!' + $words +')' + '[[:alpha:]!$%&*+./:<=>?@^_~-][[:alnum:]!$%&*+./:<=>?@^_~-]*'
# Highlight the named let expressions
(cbracket,keyword,normal,function) = `(\()(let)([[:blank:]]+)([[:alpha:]!$%&*+./:<=>?@^_~-][[:alnum:]!$%&*+./:<=>?@^_~-]*)`
# Highlight the names of defined forms
(cbracket,keyword,normal,function) = `(\()(define(?:-syntax)?)([[:blank:]]+)([[:alpha:]!$%&*+./:<=>?@^_~-][[:alnum:]!$%&*+./:<=>?@^_~-]*)`
(cbracket,keyword,normal,cbracket,function) = `(\()(define)([[:blank:]]+)(\()([[:alpha:]!$%&*+./:<=>?@^_~-][[:alnum:]!$%&*+./:<=>?@^_~-]*)`
number = '(\#(x|o|b|X|O|B))?[+-]?((0x[[:xdigit:]]+)|(([[:digit:]]*\.)?[[:digit:]]+([eE][+-]?[[:digit:]]+)?))'
cbracket = "(|)"
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