return res.to_s
end
- # Escape " \ ' and non printable characters using the rules of literal C strings and characters
+ # Escape `"` `\` `'`, trigraphs and non printable characters using the rules of literal C strings and characters
#
- # assert "abAB12<>&".escape_to_c == "abAB12<>&"
+ # assert "abAB12<>&".escape_to_c == "abAB12<>&"
# assert "\n\"'\\".escape_to_c == "\\n\\\"\\'\\\\"
+ # assert "allo???!".escape_to_c == "allo??\\?!"
+ # assert "??=??/??'??(??)".escape_to_c == "?\\?=?\\?/??\\'?\\?(?\\?)"
+ # assert "??!??<??>??-".escape_to_c == "?\\?!?\\?<?\\?>?\\?-"
#
# Most non-printable characters (bellow ASCII 32) are escaped to an octal form `\nnn`.
# Three digits are always used to avoid following digits to be interpreted as an element
b.append("\\\'")
else if c == '\\' then
b.append("\\\\")
+ else if c == '?' then
+ # Escape if it is the last question mark of a ANSI C trigraph.
+ var j = i + 1
+ if j < length then
+ var next = chars[j]
+ # We ignore `??'` because it will be escaped as `??\'`.
+ if
+ next == '!' or
+ next == '(' or
+ next == ')' or
+ next == '-' or
+ next == '/' or
+ next == '<' or
+ next == '=' or
+ next == '>'
+ then b.add('\\')
+ end
+ b.add('?')
else if c.code_point < 32 then
b.add('\\')
var oct = c.code_point.to_base(8)
# The result might no be legal in C but be used in other languages
#
# assert "ab|\{\}".escape_more_to_c("|\{\}") == "ab\\|\\\{\\\}"
+ # assert "allo???!".escape_more_to_c("") == "allo??\\?!"
fun escape_more_to_c(chars: String): String
do
var b = new Buffer