On Saturday, 13 May 2017 at 00:59:14 UTC, Stanislav Blinov wrote:
On Saturday, 13 May 2017 at 00:36:55 UTC, mogu wrote:
```d
if (null)
"1".writeln;
if ("")
"2".writeln;
if ("" == null)
"3".writeln;
```
Output:
2
3
How to understand this?
Boolean conversion on an array works on array's pointer, not
it's length. So even though `"".length == 0`, `"".ptr != null`,
and so `cast(bool)"" == true`.
```d
string s1 = null;
string s2 = "";
assert(s1 == null);
assert(s1.ptr == null);
assert(s2 == null);
assert(s2.ptr != null);
if (s1)
1.writeln;
if (s2)
2.writeln;
```
Output:
2
Thanks very much. This is a little bit confusing.
