Re: Semicolons (Re: Low-Rent Syntax)

> > while( x );/* a nasty case */
> > x--;
>
> The real problem here is not with the semicolon, it is with the grammar
> production that dominates C and Pascal:


The problem is with the compiler that fails to issue warnings about the
obvious problems with the above code:


prog.c: line 12: degenerate "while" loop
prog.c: line 13: dubious indentation level.




Tinkering with language syntax can go only a short distance towards
stamping out the bugs that typical code contains. Syntax restrictions
would be hard put to catch bugs such as:


prog.c: line 20: variable "i" may be used before set


p = malloc(strlen(s));
^
prog.c: line 32: was "strlen(s) + 1" intended?


I believe this type of diagnostic assistance, fueled by examples of
typical errors, is far more effective than adding syntactic handcuffs. I
was quite surprised to learn, this evening, of a C compiler that actually
does this level of diagnostic analysis. (Along with convenient options to
control the degree of nit-picking). Perhaps if it becomes widely
available (and demanded), compilers for other languages will do it too, to
catch errors such as:


while ( x )
y--;
endwhile;


Tom Truscott
[Which compiler is it? And when I really do want to write a degenerate
while loop, how do I tell it not to complain? -John]
--

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