that is why I am uncomfortable with C. Pascal and JALv2 are both much=20
clearer.

--Bob A
--

On 5/3/2014 11:41 AM, PICLIST wrote:
> As an experienced, but certainly not expert, C programmer - I have a few
> tens of thousands of lines of C and C++ behind me, and more in other
> languages. Unfortunately my experience is spread out over too many
> languages, years, platforms and compilers.
>
> I tend to believe in always turning on all compiler warnings and write my
> code to avoid all of the warnings. The code ends up a bit longer, but fix=
ing
> warnings has saved me from hours of debugging many times.
>
> The warnings usually tell you when you are playing around in the less
> obvious areas of the language. I am then forced to code in an obvious
> fashion so there is no question of what I want.
>
> In the current signed vs unsigned discussion, I would be forced to add an
> explicit cast to "int" or "unsigned int" depending on what I wanted. The
> cast makes the intention clear and reminds me in the future that the code=
 is
> dealing with unlike types. In fact it makes me think about the possibilit=
ies
> for error in what I am doing. In the current example for instance: Am I s=
ure
> the int will never have a value greater than 16384?
>
> Another example where the warnings are very useful is the "=3D" vs "=3D=
=3D"
> operators:
>
> It is valid C (and maybe even intentional) to code the following:
>
> // b ends up as 2!
> int a=3D1;
> int b=3D1;
>
> if (a=3Db) {
>    b=3D2;
> };
>
> In most cases this will generate a warning about using the assignment "=
=3D"
> operator in an if, instead of the more common logical "=3D=3D" comparison
> operator. The warning saves me from having to debug the problem because o=
f a
> typo.
>
> If I had really meant to do that, I would code:
>
> if (0 !=3D (a=3Db) {
>    b=3D2;
> };
>
> Or more clearly:
>
> a=3Db;
> if (a) {
>    b=3D2;
> };
>
> I even put in the extra () in the first case to be clear on what operator
> precedence I desire, since the precedence of =3D vs =3D=3D is not necessa=
rily
> obvious. Many people hate doing things like "=3D=3D 0" or "!=3D 0" in an =
if, since
> that is what the if does anyway,   but any decent compiler will create th=
e
> same code, and the clarity of specifying the "=3D=3D 0" if often worth th=
e extra
> few characters.
>
> C can be a master of obfuscation. Obfuscation is certainly not the best
> route to bug-free code. My favourite example is:
>
> #include <stdio.h>
> main(t,_,a) char *a; {
> return!0<t?t<3?main(-79,-13,a+main(-87,1-_,main(-86,0,a+1)+a)):1,
> t<_?main(t+1,_,a):3,main(-94,-27+t,a)&&t=3D=3D2?_<13?
> main(2,_+1,"%s %d %d\n"):9:16:t<0?t<-72?main(_,t,
> "@n'+,#'/*{}w+/w#cdnr/+,{}r/*de}+,/*{*+,/w{%+,/w#q#n+,/#{l+,/n{n+,/+#n+,/=
#\
> ;#q#n+,/+k#;*+,/'r :'d*'3,}{w+K w'K:'+}e#';dq#'l \
> q#'+d'K#!/+k#;q#'r}eKK#}w'r}eKK{nl]'/#;#q#n'){)#}w'){){nl]'/+#n';d}rw' i;=
# \
> ){nl]!/n{n#'; r{#w'r nc{nl]'/#{l,+'K {rw' iK{;[{nl]'/w#q#n'wk nw' \
> iwk{KK{nl]!/w{%'l##w#' i; :{nl]'/*{q#'ld;r'}{nlwb!/*de}'c \
> ;;{nl'-{}rw]'/+,}##'*}#nc,',#nw]'/+kd'+e}+;#'rdq#w! nr'/ ') }+}{rl#'{n' '=
)#
> \
> }'+}##(!!/"):t<-50?_=3D=3D*a?putchar(31[a]):main(-65,_,a+1):main((*a=3D=
=3D'/')+t,_,a
> +1)
> :0<t?main(2,2,"%s"):*a=3D=3D'/'||main(0,main(-61,*a,
> "!ek;dc i@bK'(q)-[w]*%n+r3#l,{}:\nuwloca-O;m .vpbks,fxntdCeghiry"),a+1); =
}
>
> The above is standard C and only generates one warning when I last compil=
ed
> it and really does do something. It certainly does something unexpected.
>
>

--=20
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