If the name given as parameter to local directive begins with a dot or two dots, the unique labels generated by each evaluation of macroinstruction will have the same properties.

macro testmacro reg, val=1
{
  mov reg,val
}

testmacro eax
testmacro ebx,2    

struc POINT x, y
{
  .x dd x
  .y dd y
}

mypoint1 POINT 1, 2  ;x=1 y=2
mypoint1 POINT 1     ;x=1 y=uninitialized
mypoint1 POINT , 2   ;x=uninitialized y=2    

Quote:

If the name given as parameter to local directive begins with a dot or two dots, the unique labels generated by each evaluation of macroinstruction will have the same properties.

1. What exactly does that mean?
Where's the difference when I write 'local ..num'?

2. Can I somehow give a macro-parameter a default value like this:
…

if codename eq
\codename=".text"
end if

if ~ defined bssname
\bssname=".bss"
end if

match   =bssname, bssname {\bssname=".bss"}