On 2013-11-11 10:38, Rikki Cattermole wrote:
An example of this might be:
macro foo (Context context, Ast!(string) str)
if (lexer.isSymbol(0, SymbolTypes.Class))
{
return str;
}
class Bar {
int i;
}
foo {
Bar(7);
}
The above code would succeed however the below code will give a compiler
error stating that the given macro is not found.
struct Haz {
int i;
}
foo {
Haz(9);
}
The above code is based on the assumption of a D lexer in phobos.
This is simpler set of code which won't require a lexer.
macro foo (Context context, Ast!(string) str)
if (str == "working")
{
return "";
}
foo {fails}
foo {working}
In these cases its a simple string test to determine if the text given
is specified value.
In the original example I gave, I was using regex to make the point of
validation for a given line passed to the macro.
My idea of handling errors in macros is more something like triggering a
real compile error. That could be done via the context parameter,
something like:
macro foo (Context context, Ast!(string) str)
{
if (str.eval() == "bar")
context.error("Illegal value 'bar'"); // this will trigger the
compile error
}
--
/Jacob Carlborg
