Found on mIRC 6.16, when $({,N) / $(},N) or $eval({,N) / $eval(},N) is evaluated it returns (N-1) (N-1) except when N = 0

//echo -a $({,1) * $(},2) * $eval({,3) * $eval(},4)

so? if you didnt want { } evaluated dont put them in that code..

So you can explain why { or } evaluates once to give "0 0" and twice to give "1 1"? Let's wait for someone who can give a productive response

cool

evaluating { and } seem to trigger something deep in mircs parser

perhaps you just stumbled upon one of mircs perprocessor steps?

{ xxxxxxxxxx } turns into
0 0 xxxxxxxxxx 1 1
?

or maybe im crazy

That is quite some funky stuff there.

Confirmed here, 6.16

I'd only add that this behaviour is very old, probably since $eval() was added. I always considered it to be one of those little parser quirks that I can live with.