• Dan <murpsoft hotmail.com> Apr 03 2007

Dan <murpsoft hotmail.com> writes:

I most definitely am not *for* semicolon removal/insertion.  I've been working
on the JavaScript Engine, and I've used JavaScript for a long time.  I can tell
you that *sometimes* implementing it is worse than always doing so.  You become
aware of semicolons moreso than with C/C++/C#/D languages where you can ignore
them if you automatically type them in all the time like I do.

I *am* for allowing the removal of {} for for/function when there's only one
statement.

I *am* for expression jacking some things.  Yes, a switch expression is more
complicated than a statement.  It has been done before though, and it's not
that much worse.  Also, it gets handled by the compiler and won't affect
switches that aren't expressions.

Internally, and I'm writing this terribly sub-optimally, you're saying:

// let EDX = x, AL = table offset, ECX = instruction*;

mov ECX, AL[$]; // load up the jump table
and ECX, 0x12; // sanity mask
jmp [ECX]; // jump into the jump table
mov EDX, 4; // x = switch(y){ case 3: 4; case 5: 1; case ... case ...}
jmp _out;
mov EDX, 1;
jmp _out;
...

So you're just assigning things to a variable, and passing that variable out. 
Syntactic sugar for:

switch(y){
  case 3:  x = 4;
  case 5: x = 1;
 ..
}

Which can sort of be optimized to do some cool stuff later, and theoretically
you could use EFLAGS in interesting ways throughout.