sends-on-pair(s;l;tg)
== reduce(kl,x. eqof(IdLnkDeq)(2of(kl),l)  deq-member(IdDeq;tg;map(z.1of(z);2of(s)(kl)))
==  x;false;1of(s)) 

latex

Definitions	reduce(f;k;as), p  q, p  q, eqof(d), IdLnkDeq, deq-member(eq;x;L), IdDeq, map(f;as), x.A(x), f(a), 2of(t), false, 1of(t)
FDL editor aliases	sends-on-pair