John Carter:
I'm storing the roman numerals as dchars. I have the vague hope
this is more efficient than storing them as strings.
From/to Roman numbers conversions are never performance-critical.
It looks like premature optimization.
What do you mean by "missing UCSF"?
Sorry, it's UFCS (Universal Function Call Syntax), it means
writing x.foo instead of foo(x).
I would love away around that.
http://dlang.org/phobos/std_exception.html
That's quite bad code. Better:
return roman.map!romanToDigit.array;
That certainly looks nicer, alas, dmd is unhappy....
When you have only one argument the () is not needed:
return roman.map!(a => romanToDigit(a)).array;
The cause of your error: romanToDigit is module-private. If you
make romanToDigit public the error goes away. If you use a lambda
the problem also goes away for different reasons. So in this case
using a lambda is OK.
I thought it meant just putting a ddoc /// extra / flag on the
comment,
Right. The Ddoc-produced html should show the unittest.
You can also add a module-level ddoc to your module.
return find!((a,b) =>
In most cases it's better to put a space after every comma ==>
return find!((a, b) =>
};
In D don't put a ; there for struct/classes/unions.
I think the code density of the toRomansWithZero() function is
too much low. I suggest to pack it vertically a little more. D is
not C#.
O suggest you to be more careful with size_t, your code doesn't
compile on a 32 bit system:
test.d(59): Error: cannot implicitly convert expression
(this.regionIndex) of type const(ulong) to uint
test.d(62): Error: cannot implicitly convert expression
(this.regionIndex) of type const(ulong) to uint
test.d(62): Error: cannot implicitly convert expression
(this.regionIndex) of type const(ulong) to uint
test.d(66): Error: cannot implicitly convert expression
(this.previous) of type const(ulong) to uint
So this could be better:
size_t regionIndex; /// Some digits in the system "dominate"
over others.
size_t previous; /// Hardcode link to previous digit.
I also suggest to add an ending "." to comments.
With this I think the surface review of your code is mostly done.
Bye,
bearophile
