Steven Schveighoffer:
On Tue, 15 Apr 2014 13:46:11 -0400, bearophile
What do you think are the reasons I suggested the enhancement
for?
To make people write code the way you like? :)
Honestly, it's like you require someone to call a function like:
T foo(T)(T t){return t;}
Just so you can see the foo there. I understand the idea, but
the result is not logical, just superficial.
Issue 7444 allows to tell apart the two very different operations
of this code, that look the same:
void main() {
int[][3] x;
int[] y;
int[] z;
x[] = z; // copies just the z pointer
y[] = z; // copies the elements in z
}
In Phobos there are awkward names like walkLength, and in D we
don't have a built-in "x in array" syntax, both just to tell
apart the O(1) cases from the O(n) ones. Requiring the [] when
you perform an array copy (instead of just a copy of the slice
struct) allows to visually tell apart the O(1) operations from
the O(n) ones:
void main() {
int[][3] x;
int[] y;
int[] z;
x[] = z;
y[] = z[];
}
the result is not logical, just superficial.
In D vector operations are allowed only with the [] syntax:
void main() {
int[] a, b;
a = a + b; // Wrong
a[] = a + b; // Wrong
a = a[] + b; // Wrong
a = a + b[]; // Wrong
a[] = a[] + b; // Wrong
a = a[] + b[]; // Wrong
a[] = a[] + b[]; // OK
}
A copy of the items can be seen as the simplest vector operation,
so I think it's logical for it to require the [] like the others.
Bye,
bearophile
