Vector Software Easily Writes Fail-Safe Tests
Ann S. Brandon
Here's a developer's choice: write software easily in Language A that doesn't
crash or write software easily in Language C that crashes. Vectors Software
chose Language A, which stands for Ada, rather than Language C, which stands
for, well, C.
"With C, it's very difficult to put in general purpose guards to protect
yourself from unintentional crashes," said the testing software company's
director of Engineering, John Paliotta. "In Ada, it's the reverse. It's hard to
crash an application at the operating system level, and easy to put in
exception handling that gracefully handles the error."
Vector Software, Inc., dedicated the brains and guts of its software,
VectorCAST, to Ada in 1993. The software automatically generates and
compiles code to test C/C++ and Ada components across a
comprehensive list of compilers and environments. Test cases are based
on users' requirements and include ultimate values from lowest to
highest, as well as fixed increments in between. The tests can be used
on the host, a simulator, or an embedded target.
Paliotta says that in the ten years the company has been maintaining and
changing its Ada software, they have found the code "almost impossible
to crash." VectorCAST's GUI is in C++, which has given the software
engineers many opportunities to compare the two languages as tools.
"Ada's exception handlers are better than C++," Paliotta said, explaining
the absence of random crashes. "They're general purpose. With C++ they
do not by themselves handle anomalous conditions. If at some point I
divide by zero--not intentionally, yet it happens all the time--no pre-defined
mechanisms with C++ can handle it. With Ada, it's built into the language.
If you install a small general purpose exception handler it will handle that.
Regardless of what bad thing happens it'll be caught and you'll have a
defense against an unanticipated anomaly."
Altogether, Paliotta says his department finds the Ada "standard is more
uniform and enforced across the vendors and compilers. In the C++
world everyone has their own variant." He acknowledges that C++ has an
ANSI standard, but which allows "all the compiler vendors to have their
own standard." The basis of Vector Software's choosing Ada can be
summed up, he says, as "The technology is superior."
for more on Ada.
Or write to
Ada Resource Association
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