Canonical role order (SMPTE-ish): the index of a role here is its native role_slot — the
value the C out_route copies (bus[role_slot]). Stereo = L=0, R=1; C=2 (LCR, #176);
surround appends LFE=3, Ls=4, Rs=5 later without renumbering L/R/C. Iterating an
endpoint's legs goes through THIS list, never Object.keys (which would include the trim
fields).
Canonical role order (SMPTE-ish): the index of a role here is its native
role_slot— the value the Cout_routecopies (bus[role_slot]). Stereo =L=0,R=1;C=2 (LCR, #176); surround appendsLFE=3,Ls=4,Rs=5 later without renumbering L/R/C. Iterating an endpoint's legs goes through THIS list, neverObject.keys(which would include the trim fields).