comparing foot to foot-direct.
    comparing booleans.
        ccc: T:F.
    comparing numbers.
        colors: 256, 16777216.
    comparing strings.
        initc: '\E]4;%p1%d;rgb:%p2%{255}%*%{1000}%/%2.2X/%p3%{255}%*%{1000}%/%2.2X/%p4%{255}%*%{1000}%/%2.2X\E\\', NULL.
        setab: '\E[%?%p1%{8}%<%t4%p1%d%e%p1%{16}%<%t10%p1%{8}%-%d%e48:5:%p1%d%;m', '\E[%?%p1%{8}%<%t4%p1%d%e48:2::%p1%{65536}%/%d:%p1%{256}%/%{255}%&%d:%p1%{255}%&%d%;m'.
        setaf: '\E[%?%p1%{8}%<%t3%p1%d%e%p1%{16}%<%t9%p1%{8}%-%d%e38:5:%p1%d%;m', '\E[%?%p1%{8}%<%t3%p1%d%e38:2::%p1%{65536}%/%d:%p1%{256}%/%{255}%&%d:%p1%{255}%&%d%;m'.