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@(#)pxin4.n 5.2 (Berkeley) 4/17/91
.nr H1 3 Conclusions
It is appropriate to consider, given the amount of time invested in rewriting the interpreter, whether the time was well spent, or whether a code-generator could have been written with an equivalent amount of effort. The Berkeley Pascal system is being modified to interface to the code generator of the portable C compiler with not much more work than was involved in rewritting px . However this compiler will probably not supercede the interpreter in an instructional environment as the necessary loading and assembly processes will slow the compilation process to a noticeable degree. This effect will be further exaggerated because student users spend more time in compilation than in execution. Measurements over the course of a quarter at Berkeley with a mixture of students from beginning programming to upper division compiler construction show that the amount of time in compilation exceeds the amount of time spent in the interpreter, the ratio being approximately 60/40.
A more promising approach might have been a throw-away code generator such as was done for the WATFIV system. However the addition of high-quality post-mortem and interactive debugging facilities become much more difficult to provide than in the interpreter environment.