On Fri, Mar 20, 2009 at 6:06 PM, Boyko Bantchev <[email protected]> wrote: > The point is that sh is a commmand-line interpreter (a job > control language), but not an extension language. It doesn't > do scripting in the sense of extending a compiled program. > REXX is both a c.l. interpreter and a scripting language in > this sense. And as sh was designed as (only) a c.l. interpreter, > it lacks features that would have made it a programming language > per se; so in this respect, too, it is inferior to REXX.
I have spawned shell scripts from inside perl programs to do complex tasks for the perl program. > Spawning a process to compute a single value just because it > happens to be non-integer, and then communicating this value > through a pipe or a file to another process is a replacement > to true scripting only in the sense in which all computers > are Turing machines and all programming languages are the same. But this characterization seems rather microscopic, and thus not particularly relevant. > Were it not so, there would be no point in creating and using > Tcl, Perl etc., and game programmers would have used sh and > piping where they really use, e.g., Lua. I do not think games are good examples of system integration tasks. They often have real time requirements. Meanwhile, I often write shell scripts which call perl (sometimes multiple times within the same script), and vice versa (as I mentioned, above). That said, I have seen various people comment that perl does too much and that tcl was not needed. > That aside, I don't believe the word ‘coroutine’, as used > above, is in place here. The interaction between a (compiled) > program and a script chunk does not necessarily possess the > symmetricity characteristic of coroutines. Besides, the term > ‘coroutine’ is normally used to designate a feature of a certain > programming language, such as e.g. Simula, Icon or Lua, and does > not extend to, say, communication between processes or programs > within an operating system. Ok. -- Raul ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
