note martin <p>One syntactical alternative I could think of is: <code> A &&& B # defined-and A ||| B # defined-or A >>> B # safe arrow </code> </p> <p>This would be a systematic approach reminiscent of the role of <i>undef</i> in ternary logic -- triple sign, third kind of truth value involved. </p> <p>I am not sure whether a whole lot of other similar symbols like <tt>^^^</tt> would make as much sense, though, which means we then had to explain why <em>only</em> those mentioned above were there. </p> 960147 960147