The actual change to the wording of `assert` that I intended in the previous CL.

docs/language/dartLangSpec.tex

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 and completes in the same way as the assertion.
 
 \LMHash{}
 In production mode the assertion has no effect
 and its execution immediately completes normally (\ref{completion}).
 In checked mode,
 execution of an assertion \code{\ASSERT{}($c$, $e$)} proceeds as follows:
 
 \LMHash{}
 The expression $c$ is evaluated to an object $o$.
-If the class of $o$ is not a subtype of \code{Function} then
-let $r$ be $o$.
-Otherwise,
-if the assertion occurs in the initializer list of a \CONST{} constructor,
-then we say that the assertion failed,
-otherwise let $r$ be the result of invoking $o$ with no arguments.
-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 $m$.
+If the class of $o$ is a subtype of \code{Function} and assertion occurs in the initializer list of a \CONST{} constructor,

[eernst, 2017/07/10 13:03:58]

Typo: `and [the] assertion`.

But I don't get this at all: The informal spec talks about allowing `assert` in
the initializer list of generative constructors, and they may or may not be
const. For a const constructor I'd expect that the 'condition and message
expressions in the assert must be potentially compile-time constant expressions'
which may or may not be true for that function (a static function is ok, a
function literal isn't). As a second step, we consider a specific const
constructor invocation, and that invocation will then give rise to the const
evaluation which cannot include a function call.

For a non-const instance creation expression invoking said const constructor I
would expect the function to get called (letting '$r$ be the result of invoking
$o$ with no arguments').

+then let $r$ be the result of invoking $o$ with no arguments.
+Otherwise let $r$ be $o$.
+It is a dynamic type error if $r$ is not of type \code{bool}.
+If $r$ is \TRUE{}, execution of the assert statement completes normally (\ref{completion}).
+Otherwise, $e$ 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}.
 If the assertion occurs in a \CONST{} constructor initializer list, it is a static type warning if the type of $e$ may not be assigned to \code{bool}.
 
 \rationale{Why is this a statement, not a built in function call? Because it is handled magically so it has no effect and no overhead in production mode. Also, in the absence of final methods. one could not prevent it being overridden (though there is no real harm in that).  It cannot be viewed as a function call that is being optimized away because the argument might have side effects.
 }
 
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 The invariant that each normative paragraph is associated with a line
 containing the text \LMHash{} should be maintained.  Extra occurrences
 of \LMHash{} can be added if needed, e.g., in order to make
 individual \item{}s in itemized lists addressable.  Each \LM.. command
 must occur on a separate line.  \LMHash{} must occur immediately
 before the associated paragraph, and \LMLabel must occur immediately
 after the associated \section{}, \subsection{} etc.
 
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