Re: Code Comprehension

Logan Shaw <lshaw-usenet@xxxxxxxxxxxxx> writes:

Pascal Bourguignon wrote:
So that gives:
void fun(char *a, const char *b) {
int apos = 0, i, j;
if((a==NULL)||(b==NULL)){return;}
for(i=0;a[i]!='\0';i++){
for(j=0;(b[j]!='\0')&&(a[i]!=b[j]);j++);
if(b[j]!='\0'){
a[apos++] = a[i]; }}
a[apos]='\0'; }

My god! This is twice as hard to read! You do know that whitespace
is allowed in C, right? :-) No wait, forget the smiley. I'm
serious. That is visual clutter at its worst. Whitespace is
legal for a reason, and that is to help make things clearer
by allowing the formatting to be used as a tool to help show
the structure.

I've not observed that whitespace improves anything. On the
contrary, they may be misleading. Try to understand read this:

if ( 0 == a<<1 ) { printf("yes"); }else{ printf("no"); }


Yes, that still retains some C idioms, but you have to assume
some familiarity with the language. (I noticed even you did
that, because you did not eliminate the "for" loop, which is
deep in the C idiom, and replace it with a "while" loop.)
Things like the low precedence of "||" and the fact that 0 by
itself is a legal character constant aren't very complicated
and are hard to miss if you have much experience with C.

The point is that types are important to understand code, and if you
consistenly mislead the reader by using consistenly the wrong
operations for the type, you don't help readability.


And anyway, I really doubt the more obvious C idioms are a
significant reason why many would find this code hard to read.

I've also put the ";" on its own line to draw as much attention
as possible to the fact that the "for" loop has a null body.
Putting the ";" right up against the ")", to me, just hides
that fact, which is something that needs to be highlighted.

Well that's one strong reason why to use while instead of for. But I
reserved a more violent end to that loop anyways, substituting it with
strchr.

--
__Pascal Bourguignon__
.

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