| ⊦ cstep(cs, ca, cs0) ∧ ¬ cod(ren)(cren(ca)) → repla(step, cstep, cren, ren, aren, cext, aext, (s, cs) ' + (s, cs0) ' + pcsl, cren(ca) ' + pal, ⌜as '⌝ + aσ, aα) = repla(step, cstep, cren, ren, aren, cext, aext, (s, cs0) ' + pcsl, pal, ⌜as '⌝ + aσ, aα) |