Changes http://wiki.axiom-developer.org/359MapWithBooleanDamagesMemory/diff
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Bad simple vector 0
++added:
+
+
+<hr>
+Ralf Hemmecke writes: I have commented out the above 'map' command since it
does not type match.
+
+As the output above shows 'gl' is of type 'List Equation Polynomial Integer'.
+Let us abbreviate that type by $L$.
+\begin{axiom}
+L ==> List Equation Polynomial Integer
+\end{axiom}
+
+For demonstration let
+\begin{axiom}
+t := first sol
+\end{axiom}
+removing the quotes from the following string results in a command that will
also lead to a 'System error'.
+\begin{axiom}
+"map(g +-> eval(g,t)::Boolean,gl)"
+\end{axiom}
+
+Why? The reason is the '::Boolean'. That leads to a type mismatch.
+You effectively ask for a function with the signature
+
+\begin{verbatim}
+map: (L -> Boolean, L) -> List Boolean
+\end{verbatim}
+
+but Axiom does not provide such a function.
+
+Of course, instead of causing memory damages, Axiom should rather tell you
+that it only has 'map' functions with signatures of the form
+
+\begin{verbatim}
+map: (A -> A, List A) -> List A
+\end{verbatim}
+
+(better type 'map' into hyperdoc, press 'operations' and then 'signatures').
+
+So the right way to execute what you want is:
+
+\begin{axiom}
+[[eval(g,s)::Boolean for g in gl] for s in sol]
+\end{axiom}
+
+Ooooops! Now someone tells me, why this command fails. There is a coerce
functions::
+
+ coerce: Equation Something -> Boolean
+
+So what is the problem???
+
+Maybe this gives some hint
+
+\begin{axiom}
+eqn := [eval(g,t) for g in gl]
+[c::Boolean for c in eqn]
+\end{axiom}
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