Current restrictions
The NetRexx processor is now functionally complete, though work
continues on usability and performance improvements. As of this version
there are still a number of restrictions, listed below.
Please note that the presence of an item in this section is not a
commitment to remove a restriction in some future update; NetRexx
enhancements are dependent on on-going research, your feedback, and
available resources. You should treat this list as a 'wish-list' (and
please send in your wishes).
Short-term restrictions
NetRexxC by default uses the javac compiler to generate bytecodes (class
file).
-
The 1.0 javac compiler will not let you compile a class that has the
same name as a class in java.lang. This has been fixed for 1.1.
The following problem may occur in larger methods, with Java 1.0.1 or
1.0.2 (it has been fixed in 1.1):
-
NetRexxC does not restrict the number of local variables used or
generated. However, the 1.0 javac compiler fails with unrelated
error messages (such as 'statement unreachable' or 'variable may be
uninitialized') if asked to handle more than 63 local variables.
Long term restrictions
The following restrictions are due to the use of a translator, and would
probably only be lifted if a direct-to-bytecodes NetRexx compiler were
built.
-
Externally-visible names (property, method, and class names) cannot
be Java reserved words (you probably want to avoid these anyway).
JAVAC will report these, giving the line numbers in your NetRexx
program.
-
Some binary floating point underflows may be treated as zero instead
of being trapped as errors.
-
Side-effects of calls to this() and super() in constructors may be
seen before the method and method call instructions are traced --
this is because Java does not permit tracing instructions to be
added before the call to this() or super().
-
The results of expressions consisting of the single term 'null' are
not traced.
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From 'nrinst.doc', version 1.00.
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