On Monday, 9 April 2018 at 08:27:50 UTC, Per Nordlöw wrote:
Is it possible to get the source expression sent to a lazy
function?
So that I can implement something like
show(Arg)(lazy Arg arg)
{
writeln(arg.sourceof, arg);
}
used as
show(1+2+3);
will print
1+2+3:6
Because of the way D works with a given piece of code may not
have a source-location or even a representation which is valid D
source code.
Note: There is a way to fix this but it's very involved.
Step 1: you use cow (copy-on-write) when modifying AST nodes in
semantic() or you keep distinct trees.
Step 2: you sanitize implicitly generated code to make sure it's
actually valid code.
Step 3: you write the generated code, to a well-defined location
such that source-of can point to a valid location.
also note that support for sourceof at compiletime will bloat the
executable since it needs to store the source-text.
