Help needed on script for compiling Nim programs

[edu500ac]

I am using a Makefile script for compiling Nim programs. However, RSDuck 
suggested the replacement of Makefile with nimscript. I confess that I didn't 
know anything about the very existence of nimscript, and I want to thank RSDuck 
for drawing my attention to it. However, in nimscript, I encountered the same 
kind of problem that I found in macros: The lack of simple examples. Anyway, 
here is the script I wrote:
    
    
    #!/usr/local/bin/nim
    
    mode = ScriptMode.Silent
    # Options: Silent, Verbose, Whatif
    
    let
      app=paramStr(2)
      src= app & ".nim"
      exe= app & ".x"
    
    let C= "nim c --hints:off --nimcache:xx -d:danger -o:"
    exec C & exe & " " & src
    
    mvFile exe,  "./bin/" &  exe
    
    # Usage: ./build.nims iterfib
    
    
    Run

I would appreciate feedback about the above script from members of this forum. 
The main issues are: (1) I failed in turning hints off; (2) I would like to 
print a usage message, whenever user forgets the name of the application.