sequtils.nim(786, 15) Error: expected: ':', but got: 'result'

[fxn]

This has to be a simple thing I am missing, but for some reason I am no longer 
able to import `std/sequtils`:
    
    
    tmp % cat foo.nim
    import std/sequtils
    tmp % nim c foo.nim
    Hint: used config file '/usr/local/Cellar/nim/1.6.10/nim/config/nim.cfg' 
[Conf]
    Hint: used config file 
'/usr/local/Cellar/nim/1.6.10/nim/config/config.nims' [Conf]
    ............................................................
    /usr/local/Cellar/nim/1.6.10/nim/lib/pure/collections/sequtils.nim(786, 15) 
Error: expected: ':', but got: 'result'
    
    
    Run

What could it be?