The RenderMan Interface - Paul Bourke

Comments
Any occurrence of the ’#’ character, except when in a string, indicates a comment. The comment
consists of all characters between the ’#’ and the next newline character. Comments
are treated as white space when they are encountered by the input scanner.
Numbers
Numbers include signed integers and reals. An integer consists of an optional sign (‘+’, ‘-’)
followed by one or more decimal digits. The number is interpreted as a signed decimal
integer.
A real consists of an optional sign and one or more decimal digits, with an embedded
period (decimal point), a trailing exponent, or both. The exponent, if present, consists of
‘E’ or ‘e’ followed by an optional sign and one or more decimal digits. The number is
interpreted as a real number and converted to an internal floating point value.
Strings
A string is an arbitrary sequence of characters delimited by double quote marks (‘ ” ’).
Within a string the only special characters are ‘”’ and the ‘\’ (back-slash) character. The
‘\’ character is used as an ‘escape’ to include the ‘ ” ’ character, non-printing characters, and
the ‘\’ character itself. The character immediately following the ‘\’ determines the precise
interpretation, as follows:
\n linefeed (newline)
\r carriage return
\t horizontal tab
\b backspace
\f form feed
\\ backslash
\” double quote
\ddd
character code ddd (octal)
\newline no character – both are ignored
If the character following the ‘\’ is not one of the above, the ‘\’ is ignored.
The \ddd form may be used to include any 8-bit character constant in a string. One, two, or
three octal digits may be specified (with high-order overflow ignored).
The \newline form is used to break a string into a number of lines but not have the newlines
be part of the string.
Names
Any token that consists entirely of regular characters and that cannot be interpreted as a
number is treated as a name. All characters except specials and white space can appear in
names.
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