On Sunday, 18 March 2018 at 13:10:08 UTC, Dmitry Olshansky wrote:
Do this to get the usual ptr + length:
sort!((a, b) => to!string((*a).name) <
to!string((*b).name))(recs[]);
Also to!string would be computed on each compare anew. May want
to use schwartzSort to avoid that, on 10 elements there is no
real difference though.
The 10 elements are just because it's a small test program.
What does changing "recs" to "recs[]" as the argument actually
do? Does it duplicate the fixed array on the fly? [I guess I
have to study more!]
The change does pass the compiler, but at runtime it causes a
segfault. The next to last frame in the backtrace shows (having
changed from to!string to fromStringz and using a string template
instead of a lambda):
#6 0x0000555555565760 in
std.algorithm.sorting.sort!("fromStringz((*a).name.ptr) <
fromStringz((*b).name.ptr)", 0,
testd.Record*[]).sort(testd.Record*[]) (r=...)
Then it goes through quickSortImpl, shortSort and sort5, moving
on to either std.functional.binaryFun or processing of the
lambda, with a and b equal to 0, ending with a segfault in a ??
call from fromStringz or in memcpy called from object._dup (in
the to!string case).
