cannot generate a compiled executable.

[Lqlsoftware]

mac os 10.12.5
and others are the same..etc.
╰─➤ red -c brick.red

-=== Red Compiler 0.6.2 ===-

Compiling /Users/robinlu/Documents/GitHub/community/demos/brick.red ...
...using libRedRT built on 3-Jul-2017/11:54:24+8:00
*** Compilation Error: word source not defined in system/reactivity/source
*** in file: /Users/robinlu/Documents/GitHub/community/demos/brick.red
*** near: [system/reactivity/source
srs/1 = self
srs/2 = word
set-quiet
]