Mercurial > urweb
diff doc/manual.tex @ 559:5d494183ca89
Add SQL arithmetic operators
author | Adam Chlipala <adamc@hcoop.net> |
---|---|
date | Tue, 09 Dec 2008 14:41:19 -0500 |
parents | 390cba747188 |
children | d42431608856 |
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--- a/doc/manual.tex Tue Dec 09 14:06:51 2008 -0500 +++ b/doc/manual.tex Tue Dec 09 14:41:19 2008 -0500 @@ -1198,7 +1198,7 @@ \hspace{.1in} \to \mt{sql\_exp} \; \mt{tables} \; \mt{agg} \; \mt{exps} \; (\mt{option} \; \mt{t}) \to \mt{sql\_exp} \; \mt{tables} \; \mt{agg} \; \mt{exps} \; \mt{bool} \end{array}$$ -We have generic nullary, unary, and binary operators, as well as comparison operators. +We have generic nullary, unary, and binary operators. $$\begin{array}{l} \mt{con} \; \mt{sql\_nfunc} :: \mt{Type} \to \mt{Type} \\ \mt{val} \; \mt{sql\_current\_timestamp} : \mt{sql\_nfunc} \; \mt{time} \\ @@ -1221,16 +1221,16 @@ \end{array}$$ $$\begin{array}{l} - \mt{type} \; \mt{sql\_comparison} \\ - \mt{val} \; \mt{sql\_eq} : \mt{sql\_comparison} \\ - \mt{val} \; \mt{sql\_ne} : \mt{sql\_comparison} \\ - \mt{val} \; \mt{sql\_lt} : \mt{sql\_comparison} \\ - \mt{val} \; \mt{sql\_le} : \mt{sql\_comparison} \\ - \mt{val} \; \mt{sql\_gt} : \mt{sql\_comparison} \\ - \mt{val} \; \mt{sql\_ge} : \mt{sql\_comparison} \\ - \mt{val} \; \mt{sql\_comparison} : \mt{tables} ::: \{\{\mt{Type}\}\} \to \mt{agg} ::: \{\{\mt{Type}\}\} \to \mt{exps} ::: \{\mt{Type}\} \to \mt{t} ::: \mt{Type} \\ - \hspace{.1in} \to \mt{sql\_comparison} \to \mt{sql\_exp} \; \mt{tables} \; \mt{agg} \; \mt{exps} \; \mt{t} \to \mt{sql\_exp} \; \mt{tables} \; \mt{agg} \; \mt{exps} \; \mt{t} \to \mt{sql\_exp} \; \mt{tables} \; \mt{agg} \; \mt{exps} \; \mt{bool} - \end{array}$$ + \mt{class} \; \mt{sql\_arith} \\ + \mt{val} \; \mt{sql\_int\_arith} : \mt{sql\_arith} \; \mt{int} \\ + \mt{val} \; \mt{sql\_float\_arith} : \mt{sql\_arith} \; \mt{float} \\ + \mt{val} \; \mt{sql\_neg} : \mt{t} ::: \mt{Type} \to \mt{sql\_arith} \; \mt{t} \to \mt{sql\_unary} \; \mt{t} \; \mt{t} \\ + \mt{val} \; \mt{sql\_plus} : \mt{t} ::: \mt{Type} \to \mt{sql\_arith} \; \mt{t} \to \mt{sql\_binary} \; \mt{t} \; \mt{t} \; \mt{t} \\ + \mt{val} \; \mt{sql\_minus} : \mt{t} ::: \mt{Type} \to \mt{sql\_arith} \; \mt{t} \to \mt{sql\_binary} \; \mt{t} \; \mt{t} \; \mt{t} \\ + \mt{val} \; \mt{sql\_times} : \mt{t} ::: \mt{Type} \to \mt{sql\_arith} \; \mt{t} \to \mt{sql\_binary} \; \mt{t} \; \mt{t} \; \mt{t} \\ + \mt{val} \; \mt{sql\_div} : \mt{t} ::: \mt{Type} \to \mt{sql\_arith} \; \mt{t} \to \mt{sql\_binary} \; \mt{t} \; \mt{t} \; \mt{t} \\ + \mt{val} \; \mt{sql\_mod} : \mt{sql\_binary} \; \mt{int} \; \mt{int} \; \mt{int} +\end{array}$$ Finally, we have aggregate functions. The $\mt{COUNT(\ast)}$ syntax is handled specially, since it takes no real argument. The other aggregate functions are placed into a general type family, using type classes to restrict usage to properly-typed arguments. The key aspect of the $\mt{sql\_aggregate}$ function's type is the shift of aggregate-function-only fields into unrestricted fields. @@ -1445,6 +1445,8 @@ \textrm{XML pieces} & l &::=& \textrm{text} & \textrm{cdata} \\ &&& \texttt{<}g\texttt{/>} & \textrm{tag with no children} \\ &&& \texttt{<}g\texttt{>}l^*\texttt{</}x\texttt{>} & \textrm{tag with children} \\ + &&& \{e\} & \textrm{computed XML fragment} \\ + &&& \{[e]\} & \textrm{injection of an Ur expression, via the $\mt{Top}.\mt{txt}$ function} \\ \textrm{Tag} & g &::=& h \; (x = v)^* \\ \textrm{Tag head} & h &::=& x & \textrm{tag name} \\ &&& h\{c\} & \textrm{constructor parameter} \\