Timothee Cour:
string a="ΩΩab";
auto b1=a.map!(a=>"<"d~a~">"d).array;
writeln(b1);//["<Ω>", "<Ω>", "<a>", "<b>", "", ""]
Why are there 2 empty strings at the end? (one per Omega if
you vary the
number of such symbols in the string).
The above is just weird; is that a bug?
I think it's a bug, it's shown here, I will put it in Bugzilla:
import std.stdio: writeln;
import std.algorithm: map;
import std.array: array;
void main() {
string a = "ΩΩab";
a.map!(a => "<"d ~ a ~ ">"d).writeln;
a.map!(a => "<"d ~ a ~ ">"d).array.writeln;
}
The output shows that maybe it's a problem of array():
["<Ω>", "<Ω>", "<a>", "<b>"]
["<Ω>", "<Ω>", "<a>", "<b>", "", ""]
For input ranges ranges, I don't understand why the compiler
can't accept
the foreach(i,ai;a) syntax:
it should behave as follows:
foreach(i , ai; a){expr}
rewritten as:
for(size_t i=0, ai=a.front; !a.empty; a.popFront;){expr}
but it doesn't compile (it only accepts foreach(ai;a){expr}
The idea must work in all cases. For opApply, built-in arrays,
built-in associative arrays and for ranges. I think it causes
some clashing. If you will find it causes no clashing, then it's
a candidate to become an enhancement request.
Bye,
bearophile
