Router.insert: def of bend-kit-router@0.2.0.0
Import: import bend-kit-router@0.2.0.0/router.bend as Router
Lines 219-228 of bend-kit-router@0.2.0.0/router.bend: https://jend.leeeet.dev/read.txt?path=bend-kit-router@0.2.0.0/router.bend&start_line=219&end_line=228

import Base

# ponytail: preparation merges shapes in O(routes²); replace with a shape index if construction becomes a bottleneck.
def insert(~A: Data, paths: List<&2, Path<A>>, +entry: Handler<A>, +groups: List<&2, U32>) -> Result<&2, &2, Error, List<&2, Path<A>>>:
  match paths:
    case Nil{}:
      Handler{method, pattern, +ss, action} = entry
      Done{[Path{ss, [Handler{method, pattern, ss, action}], groups, ""}]}
    case Path{+ss, +handlers, +old_groups, +allow} <> +t:
      Handler{+method, +pattern, +es, +action} = entry
      candidate = {Handler{method, pattern, es, action} : Handler<A>}
      insert.branch(~A, shape(ss, es), ss, handlers, old_groups, allow, t, candidate, groups, u => insert(~A, t, Handler{method, pattern, es, action}, groups))

Uses (8):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Result
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32
  https://jend.leeeet.dev/definition.txt?path=bend-kit-router@0.2.0.0/router.bend&name=Error
  https://jend.leeeet.dev/definition.txt?path=bend-kit-router@0.2.0.0/router.bend&name=Handler
  https://jend.leeeet.dev/definition.txt?path=bend-kit-router@0.2.0.0/router.bend&name=Path
  https://jend.leeeet.dev/definition.txt?path=bend-kit-router@0.2.0.0/router.bend&name=insert.branch
  https://jend.leeeet.dev/definition.txt?path=bend-kit-router@0.2.0.0/router.bend&name=shape