Re: How to complex switch?

[KennyTM~]

On May 12, 11 19:13, Matthew Ong wrote:

Hi All,

Anyway to include this cool feature of switch with D in the near future?

Why the obsession with 'switch'? 'if' works fine.

switch(str){
                    // regexp
case "abc", "def", "as+b?": s1(); break;

case "za+", "wd?", "aaa": s2(); break;

default: s3();
}

Regex isn't even a built-in feature, why would a 'switch' should support it.

if (match(str, regex("abc|def|as+b?"))
  s1();
else if (match(str, regex("za+|wd?|aaa"))
  s2();
else
  s3();

switch (tag) {
default: s3()
case 0, 1, 2, 3: s1()
case 4, 5, 6, 7: s2()
}

Already possible (except you're missing the 'break;')

switch (x := f();) {  // missing switch expression means "true"
case x<  0: return -x
default: return x
}

Please no. Why introduce yet another operator ':=' ?!

auto x = f();
if (x < 0)
  return -x;
else
  return x;

switch (x){
case x<  y: f1()
case x<  z: f2()
case x == 4: f3()
case z+y: f4()
}

Assume you don't mean to fall-through

if (x < y)
   f1();
else if (x < z)
   f2();
else if (x == 4)
   f3();
else if (x == z+y)
   f4();