Index: docs/language/dartLangSpec.tex |
diff --git a/docs/language/dartLangSpec.tex b/docs/language/dartLangSpec.tex |
index 54b5b3c8698889bbc2877937490fcb0cafa96d86..a01d8eb2d9c4a9a652bc909f2ef32efd54afa749 100644 |
--- a/docs/language/dartLangSpec.tex |
+++ b/docs/language/dartLangSpec.tex |
@@ -6593,19 +6593,24 @@ An {\em assert statement} is used to disrupt normal execution if a given boolean |
\begin{grammar} |
{\bf assertStatement:} |
- assert `(' expression `)' `{\escapegrammar ;}' |
+ assert `(' expression ( `,` expression )? `)' `{\escapegrammar ;}' |
. |
\end{grammar} |
\LMHash{} |
-The assert statement has no effect in production mode. In checked mode, execution of an assert statement \code{\ASSERT{}($e$);} proceeds as follows: |
+An assert statement on the form \code{\ASSERT($e$);)} is equivalent to a statment on the form \code{\ASSERT($e$, null);}. |
\LMHash{} |
-The expression $e$ is evaluated to an object $o$. If the class of $o$ is a subtype of \code{Function} then let $r$ be the result of invoking $o$ with no arguments. Otherwise, let $r$ be $o$. |
-It is a dynamic type error if $o$ is not of type \code{bool} or of type \code{Function}, or if $r$ is not of type \code{bool}. If $r$ is \FALSE{}, we say that the assertion failed. If $r$ is \TRUE{}, we say that the assertion succeeded. If the assertion succeeded, execution of the assert statement is complete. If the assertion failed, the execution throws (\ref{completion}) an \code{AssertionError} with a stack trace corresponding to the current execution state at the \ASSERT{} statement. |
+The assert statement has no effect in production mode. In checked mode, execution of an assert statement \code{\ASSERT{}($c$, $e$);} proceeds as follows: |
-%\Q{Might be cleaner to define it as \code{if (!$e$) \{\THROW{} \NEW{} AssertionError();\}} (in checked mode only). |
-%What about an error message as part of the assert?} |
+\LMHash{} |
+The expression $c$ is evaluated to an object $o$. If the class of $o$ is a subtype of \code{Function} then let $r$ be the result of invoking $o$ with no arguments. Otherwise, let $r$ be $o$. |
+It is a dynamic type error if $o$ is not of type \code{bool} or of type \code{Function}, or if $r$ is not of type \code{bool}. |
+If $r$ is \FALSE{}, we say that the assertion failed. |
+If $r$ is \TRUE{}, we say that the assertion succeeded. |
+If the assertion succeeded, execution of the assert statement completes normally (\ref{completion}). |
+If the assertion failed, $e$ is evaluated to an object $m$. |
+Then the execution of the assert statement throws (\ref{completion}) an \code{AssertionError} containing $m$ and with a stack trace corresponding to the current execution state at the \ASSERT{} statement. |
\LMHash{} |
It is a static type warning if the type of $e$ may not be assigned to either \code{bool} or $() \rightarrow$ \code{bool}. |