<id-body-char> ::= <id-start-char> @! <digit-char>
-<alpha-char> ::= "A" | "B" | \dots\ | "Z"
-\alt "a" | "b" | \dots\ | "z"
-\alt <extended-alpha-char>
+<alpha-char> ::= "A" | "B" $| \cdots |$ "Z"
+ | "a" | "b" $| \cdots |$ "z"
+ | <extended-alpha-char>
<digit-char> ::= "0" | <nonzero-digit-char>
-<nonzero-digit-char> ::= "1" | "2" $| \ldots |$ "9"
+<nonzero-digit-char> ::= "1" | "2" $| \cdots |$ "9"
\end{grammar}
The precise definition of @<alpha-char> is left to the function
<char-literal> ::= "'" <char-literal-char> "'"
-<string-literal-char> ::= any character other than "\\" or "\""
-\alt "\\" <char>
+<string-literal-char> :: "\\" <char>
+ | any character other than "\\" or "\""
-<char-literal-char> ::= any character other than "\\" or "'"
-\alt "\\" <char>
+<char-literal-char> :: "\\" <char>
+ | any character other than "\\" or "'"
<char> ::= any single character
\end{grammar}
\begin{grammar}
<integer-literal> ::= <decimal-integer>
-\alt <binary-integer>
-\alt <octal-integer>
-\alt <hex-integer>
+ | <binary-integer>
+ | <octal-integer>
+ | <hex-integer>
<decimal-integer> ::= "0" | <nonzero-digit-char> @<digit-char>^*
-<binary-integer> ::= "0" @("b"|"B"@) @<binary-digit-char>^+
+<binary-integer> ::= "0" @("b" @! "B"@) @<binary-digit-char>^+
<binary-digit-char> ::= "0" | "1"
-<octal-integer> ::= "0" @["o"|"O"@] @<octal-digit-char>^+
+<octal-integer> ::= "0" @["o" @! "O"@] @<octal-digit-char>^+
-<octal-digit-char> ::= "0" | "1" $| \ldots |$ "7"
+<octal-digit-char> ::= "0" | "1" $| \cdots |$ "7"
-<hex-integer> ::= "0" @("x"|"X"@) @<hex-digit-char>^+
+<hex-integer> ::= "0" @("x" @! "X"@) @<hex-digit-char>^+
<hex-digit-char> ::= <digit-char>
-\alt "A" | "B" | "C" | "D" | "E" | "F"
-\alt "a" | "b" | "c" | "d" | "e" | "f"
+ | "A" | "B" | "C" | "D" | "E" | "F"
+ | "a" | "b" | "c" | "d" | "e" | "f"
\end{grammar}
Sod understands only integers, not floating-point numbers; its integer syntax
\subsection{Punctuation} \label{sec:syntax.lex.punct}
\begin{grammar}
-<punctuation> ::= any nonalphanumeric character other than "_", "\"" or "'"
+<punctuation> ::= "\dots"
+\alt any nonalphanumeric character other than "_", "\"", or "'"
\end{grammar}
\subsection{Comments} \label{sec:syntax.lex.comment}
\begin{grammar}
-<comment> ::= <block-comment>
-\alt <line-comment>
+<comment> ::= <block-comment> | <line-comment>
<block-comment> ::=
"/*"
<property> ::= <identifier> "=" <expression>
-<expression> ::= <term> | <expression> "+" <term> | <expression> "--" <term>
+<expression> ::= <additive>
-<term> ::= <factor> | <term> "*" <factor> | <term> "/" <factor>
+<additive> ::= <term>
+ | <additive> "+" <term>
+ | <additive> "--" <term>
-<factor> ::= <primary> | "+" <factor> | "--" <factor>
+<term> ::= <factor>
+ | <term> "*" <factor>
+ | <term> "/" <factor>
+
+<factor> ::= <primary>
+ | "!" <factor> | "~" factor
+ | "+" <factor> | "--" <factor>
<primary> ::=
<integer-literal> | <string-literal> | <char-literal> | <identifier>
-\alt "<" <plain-type> ">"
-\alt "{" <c-fragment> "}"
-\alt "?" <s-expression>
-\alt "(" <expression> ")"
+\alt "<" <plain-type> ">" | "{" <c-fragment> "}" | "?" <s-expression>
+ | "(" <expression> ")"
\end{grammar}
\emph{Property sets} are a means for associating miscellaneous information
\item The @|boolean| output type denotes a boolean value, which may be either
true or false. A value of type @|id| is considered true if it is @|true|,
- @|t|, @|yes|, @|on|, or @|verily|; or false if it is @|false|, @|nil|,
- @|no|, @|off|, or @|nowise|; it is erroneous to provide any other
- identifier where a boolean value is wanted. A value of type @|int| is
- considered true if it is nonzero, or false if it is zero.
+ @|t|, @|yes|, @|on|, @|yup|, or @|verily|; or false if it is @|false|,
+ @|nil|, @|no|, @|off|, @|nope|, or @|nowise|; it is erroneous to provide
+ any other identifier where a boolean value is wanted. A value of type
+ @|int| is considered true if it is nonzero, or false if it is zero.
\item The @|symbol| output type denotes a Lisp symbol.
upper; if the name contains letters of both cases, then it is not changed.
For example, @|foo45| becomes @|FOO45|, or \emph{vice-versa}; but @|Splat|
remains as it is. Second, the name is subjected to \emph{separator
- switching}: all underscores in the name are replaced with hyphens (and
+ switching}: all underscores in the name are replaced with hyphens (and
\emph{vice-versa}, though hyphens aren't permitted in identifiers in the
first place). Finally, the resulting name is interned in the current
package, which will usually be @|sod-user| unless changed explicitly by the
class. It is an error if any of these @<identifier>s does not name a defined
class. The superclass list is required, and must not be empty; listing
@|SodObject| as your class's superclass is a good choice if nothing else
-seems suitable. It's not possible to define a \emph{root class} in the Sod
-language: you must use Lisp to do this, and it's quite involved.
+seems suitable. A class with no direct superclasses is called a \emph{root
+class}. It is not possible to define a root class in the Sod language: you
+must use Lisp to do this, and it's quite involved.
The @<properties> provide additional information. The standard class
properties are as follows.