What the heck is wrong with CTFE's?

[JS]

Ultimately, the point is, that I thought CTFE's were suppose to 
be compile time runnable functions. The problem is, the actual 
language grammar changes. can use i++ as an argument to a 
template at runtime without issue but not at compile time... and 
since this seems to be the case from the examples I've posted, 
this causes, at least for me, a lot of confusion. (who knows what 
other differences there are) (and IMO they are flaws in the CTFE 
system... although maybe there is some deep underlying reason why 
it must be done that way)