Re: foreach, is and pointer

2017-03-26 Thread rikki cattermole via Digitalmars-d-learn 

On 26/03/2017 7:52 AM, helxi wrote:

What's the difference between
1.
string x = "abcd";
foreach(character; x)
write(character);

and

string x = "abcd";
foreach(character; x[0..$])
write(character);


Hopefully the compiler is smart enough to ignore that slice (since its 
identical in purpose).



2. is and ==


is: bit for bit comparison
==: "magic" comparison logic, supports e.g. opEquals on classes.


3. pointer and address and reference?


pointer: a place in memory! or hdd.. or well pretty much anywhere the 
kernel maps it to, just assume that there is some data there that you 
may be able to do some, all or none of these things read, write, 
execute. May also be invalid aka null aka 0.


reference: pointer + some other pointer generally, e.g. class instance 
data pointer + typeinfo reference + vtable.

foreach, is and pointer

2017-03-26 Thread helxi via Digitalmars-d-learn 

What's the difference between
1.
string x = "abcd";
foreach(character; x)
write(character);

and

string x = "abcd";
foreach(character; x[0..$])
write(character);

2. is and ==

3. pointer and address and reference?