On 08/12/2016 04:06 PM, Shachar Shemesh wrote:
On 12/08/16 22:55, Walter Bright wrote:
I'm surprised that I've never seen anyone else use such a technique.
It's so unusual I've seen it be unrepresentable in some 'make'
replacements.
I suppose it's like unittest and ddoc. Sure, you can do it with some
contortions and/or some external tooling, but having it conveniently
built in to the language changes everything.
Actually, even with it being easilly accessible in the compiler, there
are sometimes reasons to still do it with an external tool.
My next task at work requires precomputing a table. This might prove to
be a quite intensive task, and the result will change quite rarely.
Under those circumstances, I believe I will not wish to compute it each
time the system is compiled, but to compute it when it changes and use a
cached version.
I wonder if you can arrange things such that a compile-time table is
computed only upon a change in the source file. I mean:
// table.di
extern double[] table;
// table.d
double[] table = makeComplicatedTable();
double[1024] makeComplicatedTable() {
... compile-time computation ...
}
People use the interface file table.di. The complicated computation goes
in table.o which is generated only when table.d is changed.
Andrei
