I hope I didn't miss anything; I copied it from the book.
import std.stdio, std.exception;
interface Stat{
void accumulate(double x);
void postprocess();
double result();
}
class Min : Stat{
private double min = double.max;
void accumulate(double x){
if( x < min ){
min = x;
}
}
void postprocess(){ }
double result(){
return min;
}
}
void main(string[] args){
Stat[] stats;
foreach(arg; args[1 .. $]){
auto newStat = cast(Stat) Object.factory("stats." ~ arg);
enforce(newStat, "Invalid statistics function: " ~ arg);
stats ~= newStat;
}
for(double x; stdin.readf(" %s ", &x) == 1; ){
foreach(s; stats){
s.accumulate(x);
}
}
foreach(s; stats){
s.postprocess();
writeln(s.result());
}
}
On Thu, Dec 23, 2010 at 6:04 PM, Andrei Alexandrescu <
[email protected]> wrote:
> On 12/23/10 5:50 PM, Caligo wrote:
>
>>
>>
>> On Thu, Dec 23, 2010 at 5:38 PM, Andrej Mitrovic
>> <[email protected] <mailto:[email protected]>> wrote:
>>
>> On 12/24/10, Caligo <[email protected]
>> <mailto:[email protected]>> wrote:
>> > You got me excited, so I decided to give GDC another try. I
>> cloned the
>> > repo, and using GCC 4.4.5, it compiled without errors.
>> > I started following the examples in TDPL, but the Stat program on
>> page 22
>> > gives the following errors:
>> >
>> > t1.d:33: Error: void has no value
>> > t1.d:33: Error: incompatible types for ((readf(" %s ",& x)) ==
>> (1)): 'void'
>> > and 'int'
>> >
>> > is there a typo in the code, or is this some kind of bug in GDC?
>>
>> Use stdin.readf:
>>
>> import std.exception, std.stdio;
>> void main(string[] args) {
>> for (double x; stdin.readf(" %s ", &x) == 1; ) {
>> }
>> }
>>
>> The TDPL errata is here btw, that bug is listed:
>> http://erdani.com/tdpl/errata/index.php?title=Main_Page
>>
>>
>>
>> great, that fixed the problem. I was actually trying to find the errata
>>
>> too, so thanks for that.
>>
>> The example compiles but it throws an exception:
>>
>> >> echo 3 4 6.6 7.7 33.4 | ./t1 Min Max Average
>> [email protected]@30
>>
>
> Would you mind posting the entire code? Thanks.
>
> Andrei
>
