On 12/08/2011 08:55 AM, Walter Bright wrote:
On 12/7/2011 11:11 PM, Robert Jacques wrote:
On Wed, 07 Dec 2011 23:27:41 -0500, Jay Norwood <j...@prismnet.com>
wrote:
I've been reading about the use of expression templates in this blitz
page,
which provides arrays implemented by c++ templates. They have some
convenient
features, such as array initialization with auto-incrementing array
index
values in the expressions and applying a cast operator to an entire
array
within an expression. Do D built-in array operations and initialization
include these type of features, or would you need to create some
similar D
template implementation to guarantee the efficient expression
evaluation and
similar initialization features?
http://www.oonumerics.org/blitz/docs/blitz_3.html#SEC80
Built-in? No, not everything. But std.range, std.array and
std.algorithm have a
lot of the convenience features you're looking for. Actual D array
operations,
i.e. x[] = y[] + z[] * b;, are more efficient than expression templates.
Currently, what you can do in an array op is somewhat limited, but
generalization, i.e. x[] = sin(iota(0,x.length)[]) + y[] is on Don's
todo list.
I'll add that you can do expression templates in D, but there's no point
to them.
Expression templates in D are syntactically more limited because it is
impossible to overload the 'not' and comparison operators. Why is there
no point to them?
