• Dfr (6/6) Dec 08 2013 Does D has somtething similar ?
• qznc (13/19) Dec 09 2013 No, not in general. There are a few special cases, though.
• Dfr (14/16) Dec 09 2013 Sorry, it was misnomer in topic title. But simultaneous
• qznc (11/22) Dec 09 2013 Afaik, D has no StatementExpression, which means no declarations
• Andrea Fontana (8/15) Dec 10 2013 Ok then write:

"Dfr" <deflexor yandex.ru> writes:

Does D has somtething similar ?

http://code.google.com/p/go-wiki/wiki/SimultaneousAssignment

I tried this way, but it not worked out.

if((int x = 10) > 0) {
     writefln("x is %s", x);
}

"qznc" <qznc web.de> writes:

On Monday, 9 December 2013 at 07:38:04 UTC, Dfr wrote:
 Does D has somtething similar ?

 http://code.google.com/p/go-wiki/wiki/SimultaneousAssignment

No, not in general. There are a few special cases, though.

The foreach loop can assign value and index simultaneously.

   foreach (int i, char c; a) {
     writefln("a[%d] = '%c'", i, c);
   }

Many things can be done in the library. For example, the variable 
swap from your link:

   swap(i,j);     // more: http://www.dpaste.dzfl.pl/582f7ae2

For returning multiple values from a function in D, you use 
std.typecons.tuple.

 I tried this way, but it not worked out.

 if((int x = 10) > 0) {
     writefln("x is %s", x);
 }

Could you give more context for your specific example? What are 
you trying to do?

"Dfr" <deflexor yandex.ru> writes:

Sorry, it was misnomer in topic title. But simultaneous 
assignment also useful topic to learn.

What i trying to achieve in my current example is more succinct 
code.
A coming from Perl and instead of writing:

if(some_complex_statement.here > 0) {
     writefln("x is %s", some_long_expression.here);
}

I got used not to repeat complex statement, but use 'x' as quick 
alias:

if((int x = some_complex_statement.here) > 0) {
     writefln("x is %s", x);
}


On Monday, 9 December 2013 at 08:28:48 UTC, qznc wrote:
 Could you give more context for your specific example? What are 
 you trying to do?

"qznc" <qznc web.de> writes:

On Monday, 9 December 2013 at 09:32:26 UTC, Dfr wrote:
 What i trying to achieve in my current example is more succinct 
 code.
 A coming from Perl and instead of writing:

 if(some_complex_statement.here > 0) {
     writefln("x is %s", some_long_expression.here);
 }

 I got used not to repeat complex statement, but use 'x' as 
 quick alias:

 if((int x = some_complex_statement.here) > 0) {
     writefln("x is %s", x);
 }

Afaik, D has no StatementExpression, which means no declarations 
inside expressions. However, there is an AssignExpression, so 
assignment works, but requires the declaration before.

   int x;
   if((x = some_long_expression.here) > 0) {
     writefln("x is %s", x);
   }

The bad news is that this means type inference cannot be used 
here (no "auto") and the variables is declared in a wider scope 
than just the if-body.

"Andrea Fontana" <nospam example.com> writes:

On Monday, 9 December 2013 at 13:57:04 UTC, qznc wrote:
   int x;
   if((x = some_long_expression.here) > 0) {
     writefln("x is %s", x);
   }

 The bad news is that this means type inference cannot be used 
 here (no "auto") and the variables is declared in a wider scope 
 than just the if-body.

Ok then write:

{
   auto x = some_long_expression.here;
   if (x > 0) {
     writefln("x is %s", x);
   }
}