On 03/25/2016 11:32 AM, Adam D. Ruppe via Digitalmars-d-learn wrote:
On Friday, 25 March 2016 at 18:25:28 UTC, Charles Hixson wrote:
But when I try to cast a Chnk to a ubyte[], I get an error, and
rawWrite takes a generic array of anything... you should be able to
rawWrite((&your_object)[0 .. 1])
Thanks, that compiled. It's running a test now...and I'm leaving it
for a few hours.
And that worked, but suddenly (after a compiler upgrade, did that
matter? I'd also changed the program, though in ways that shouldn't have
affected this.) it stopped working with the message:
let4a.d(138): Error: no [] operator overload for type Chnk
Well, there isn't, Chnk is just a struct.
The offending line was:
f.rawWrite (&(val)[0..1]);
which I already though was unreasonably convoluted. I just wanted
something like:
f.write(&val, val.sizeof);
which used to work, but the corresponding read doesn't seem to exist
anymore, so I can't test it. It's documented, but when I try to use it:
f.read(&c, c.sizeof);
results in:
let4a.d(172): Error: template std.file.read cannot deduce function from
argument types !()(File, Chnk*, ulong), candidates are:
/usr/include/dmd/phobos/std/file.d(222): std.file.read(R)(R name,
size_t upTo = size_t.max) if (isInputRange!R &&
isSomeChar!(ElementEncodingType!R) && !isConvertibleToString!R)
/usr/include/dmd/phobos/std/file.d(248): std.file.read(R)(auto ref R
name, size_t upTo = size_t.max) if (isConvertibleToString!R)
And I'm trying to do a binary read, not a string read. (I also tried it
with f.read(c, c.sizeof); and got equivalent error messages.
And the struct was (abbreviated as noted):
struct Chnk
{
char[20] wrd;
ubyte length;
ulong id;
this (ulong id, string wrd) { ... }
uint hCode () { return hash(wrdStr) % fcnt; }
string toString () { ... }
string wrdStr() { ... }
} // struct Chnk
There are no indirections. It's just a simple struct that I want to
read and write to a randomly accessible file. This used to be easy, but
now I keep running into problems.
FWIW, it's stored in a ChnkTbl, thus:
const ushort fcnt = 128;
alias Chnk[string] ChnkTbl;
ChnkTbl[fcnt] chnks;
with the idea that each ChnkTbl would be stored in a separate file. But
it's the binary read/write I keep having problems with.
