Learning Nim - some problems with nested template / macro / generic code

[icebergg]

I'm checking out Nim, have read most of the manual - there are a lot of things 
I like! I'm however having problems with nested template / macro / generic 
code, which I do not know why it doesn't work:
    
    
    import iterrr
    
    proc testIterrr() =
        let m = @[1, 2, 3].items.iterrr:
            max()
        echo m
    
    testIterrr()
    
    
    Run

This works when the routine is a proc or the code's outside of the routine, but 
not when it's a template or a generic proc, with the error deep inside `iterrr` 
macros.

My mental model is that a template is essentially copy pasting its body into 
callsite, with the exception that symbols can be renamed for hygene and what 
symbols can be early bound are early bound. AFAIK neither of these can explain 
the template above failing: the scope of the definition site and callsite is 
the same, and there are no conflicts in symbol names. What's the reason for it 
failing?

Another similar example, seemingly crashing the compiler:
    
    
    import zero_functional
    
    template time(runs: int, code: typed): void =
        let start = cpuTime()
        code
        for i in 1..runs:
            code
        let endd = cpuTime()
        echo "bench took: ", endd - start
    
    time(1_000_000):
        discard
            @[1] -->
            all(it mod 3 == 0)
    
    
    Run

This compiles outside of the `time` template, inside fails with
    
    
    
...........................................................................................................assertions.nim(34)
       raiseAssert
    Error: unhandled exception: ccgtypes.nim(210, 17) `false` mapType: 
tyAnything [AssertionDefect]
    
    
    Run

Thanks for the help!