pub const IGNORED_EDGE_KEY: &str = "\u{1}ignorededge";Expand description
Edge attribute set by a layout on an edge it routed although its type is IGNORED
(dot’s orthoEdges under concentrate, which keeps the first edge of each node pair
whatever its type): renderers draw its spline (emit_edge_graphics has no type check),
but attach_attrs_and_arrows gives it no pos, lp, xlp, head_lp or tail_lp
(lib/common/output.c). The layout keeps the edge’s input label positions under
IGNORED_EDGE_INPUT_KEYS, since it may overwrite them to draw the labels.