SICStus Prolog

`quoted-name`	::= `quoted-atom`

`base-prefix`	::= `base` `'`	{indicates base `base` }

`base`	::= `digit...`	{ in the range [2..36] }

`char-item`	::= `char`	{ other than `\` }
	\| `\` `escape-sequence`	{ unless character escapes have been switched off }

`other-escape-sequence`	::= `x` `alpha` `alpha`	{treating a,b,... and A,B,... as 10,11,... in the range [0..15], hex character code }
	\| `digit` `?digit` `?digit`	{ in the range [0..7], octal character code }
	\| `^` ?	{ delete, character code 127 }
	\| `^` `alpha`	{ where `alpha` must be a letter, stands for the control character `alpha` mod 32 }
	\| `c` `?layout-char`...	{ ignored }
	\| `layout-char`	{ ignored }
	\| `char`	{ other than the above, stands for itself }

`quoted-char`	::= `layout-char`
	\| `printing-char`