Visgraph.key: def of bend-visgraph@2.0.0.0
Import: import bend-visgraph@2.0.0.0/visgraph.bend as Visgraph
Lines 221-227 of bend-visgraph@2.0.0.0/visgraph.bend: https://jend.leeeet.dev/read.txt?path=bend-visgraph@2.0.0.0/visgraph.bend&start_line=221&end_line=227

import Base

# What a later point must beat to pop y. An equal point beats nothing, so an
# interval's first highest point is its pivot. A NaN beats nothing either,
# and ts2vg's argmax takes it only as an interval's first point, so a NaN at
# i is the pivot of the right side of i - 1: it takes the key of the entry
# below it and leaves the stack with that entry.
def key(+y: F32, +below: F32) -> F32:
  pick(is_nan(y), below, y)

Uses (3):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=F32
  https://jend.leeeet.dev/definition.txt?path=bend-visgraph@2.0.0.0/visgraph.bend&name=is_nan
  https://jend.leeeet.dev/definition.txt?path=bend-visgraph@2.0.0.0/visgraph.bend&name=pick