On Sunday, 13 August 2017 at 08:09:28 UTC, Petar Kirov
[ZombineDev] wrote:
On Sunday, 13 August 2017 at 07:37:15 UTC, data pulverizer
wrote:
Hi all,
Is it possible to launch/spawn a thread/fibre or some other
appropriate item and obtain an immutable/enum or some
appropriate output at compile-time? For instance return an
immutable(string) from the external thread to be used as the
input to a template parameter or a CTFE function. To be clear
the thread carries out run-time processing e.g. reading a file.
Thanks in advance.
No, CTFE is single-threaded and additionally it is required
that functions executed at compile-time are "pure", i.e. they
don't affect the global state of the system and don't use any
non-portable facilities. Essentially, only pure computation is
allowed.
Though, specifically reading files is allowed at compile-time
via the `string s = import("file.txt");` syntax, provided that
the file `file.txt` is located in a directory, specified to the
compiler by the `-J` flag. For more information see:
http://dlang.org/spec/expression.html#import_expressions
Thank you. Great explanation!
