On Tuesday, 6 February 2018 at 18:33:02 UTC, Ralph Doncaster
wrote:
I've been reading std.conv and std.range, trying to figure out
a high-level way of converting a hex string to bytes. The only
way I've been able to do it is through pointer access:
import std.stdio;
import std.string;
import std.conv;
void main()
{
immutable char* hex = "deadbeef".toStringz;
for (auto i=0; hex[i]; i += 2)
writeln(to!byte(hex[i]));
}
While it works, I'm wondering if there is a more
object-oriented way of doing it in D.
After a bunch of searching, I came across hex string literals.
They are mentioned but not documented as a literal.
https://dlang.org/spec/lex.html#string_literals
Combined with the toHexString function in std.digest, it is easy
to convert between hex strings and byte arrays.
import std.stdio;
import std.digest;
void main() {
auto data = cast(ubyte[]) x"deadbeef";
writeln("data: 0x", toHexString(data));
}
p.s. the cast should probably be to immutable ubyte[]. I'm
guessing without it, there is an automatic copy of the data being
made.
