On Thursday, 4 July 2013 at 09:24:53 UTC, TommiT wrote:
Yes, you are right in that the quote from TDPL refers to that
specific function signature and is saying that the base type of
T[] and T must match. But more generally, that quote is also
saying that D doesn't try to do implicit conversion and type
deduction at the same time for type-parameterized runtime
arguments. In other words, the quote is saying: the type of the
argument you pass to a templated function must match exactly to
the templated type that the function template is expecting for
that particular argument. That is: no implicit conversion
happens to your variable before it is passed to the function as
a runtime argument whose type is parameterized by the function.
You heavily misunderstoond the topic. The issue here is that in
T[] find(T)(T[] haystack, T needle)
type of neendle should correspond to base type of haystack. If
there is a contradiction ("at the same time implicit conversions
and type deduction"), dmd issues error. But here
void foo(T)(T[] slice) { }
base type of slice is not tied to any other parameters. Actually
if you pass integer static array, dmd deduces T to be int, then
template instantiation part is done. After that static array is
casted to slice as what happens with non-template function
(internally dmd treats it like foo(cast(int[])arr)). Other your
comments are based on this misunderstanding.
