Steve Ferg wrote: > Is there any particular reason why this might be a *bad* language- > design idea?
Syntactically, using braces, begin/end blocks, python white space, and your if/elif/then/endif structures, amounts to the same thing; they are all equivalent. Thus from a language pov, there's no compelling reason to do one over the other. One good reason to avoid the if/elif/then/endif syntax and its related friends in a language (while/wend, do/loop, for/next) is that they require parser support for what amounts to three or four versions of precisely the same construct: the block. Thus from a parser or compiler point of view, it's far better and easier to have blocks begin and end with something that is consistent and recognizable without a lot of look-ahead or context. I once started to write a parser for the QuickBasic language but found very quickly that the grammar required a fair amount of token look-ahead. For example, if I found the token "End", I had to look at least one token ahead to find out if this was an "end if" or just an "end." Also "end" could, if I recall, have an optional number parameter that would set the exit errorlevel code. Certainly QuickBasic was not context-free and was not LL(1). I'm not sure, but Python's grammar is LL(1) I think, and probably darn close to context-free. -- http://mail.python.org/mailman/listinfo/python-list
