On Saturday, 13 January 2018 at 04:17:02 UTC, Joe wrote:
It only compiled after I removed the second 'const' in the
first and second arguments.
Yeah, D's const applies down the chain automatically, so you
don't write it twice there.
string[] keywords = ["hostaddr", "port", "dbname"];
string[] values = ["127.0.0.1", "5432", "testdb"];
conn = PQconnectdbParams(cast(const char **)kws,
cast(const char **)vals, 1);
So my question is: is there an easier or better way of passing
two arrays of C null-terminated strings to an extern(C)
function?
If and only if the values are known at compile time, you can do:
const char** keywords = ["hostaddr".ptr, "port".ptr,
"dbname".ptr, null].ptr;
or even do it inline:
PQconnectdbParams(["hostaddr".ptr, "port".ptr, "dbname".ptr,
null].ptr, ditto_for_values, 1);
Otherwise, what you did there is decent... being a C style of
array of arrays, it will need to be coded in a C style with stuff
like malloc and toStringz to convert D to C strings too.
