Concat.onto.next: def of bolt@1.27.0.0
Import: import bolt@1.27.0.0/src/rules/suspicious/concat.bend as Concat
Lines 64-72 of bolt@1.27.0.0/src/rules/suspicious/concat.bend: https://jend.leeeet.dev/read.txt?path=bolt@1.27.0.0/src/rules/suspicious/concat.bend&start_line=64&end_line=72

import Base
import bolt@1.27.0.0/src/syntax/lex.bend as Lex
import bolt@1.27.0.0/src/syntax/tree.bend as Tree
import bolt@1.27.0.0/src/rules/calls.bend as Calls

# a first cell, then the second: a name then `++`, or a call
def onto.next(+hh: Tree.Node, h2: Tree.Node) -> Maybe<&2, Lex.Tok>:
  match h2:
    case Tree.Leaf{Lex.Tok{k, +o, _l, _c}}:
      Bool.pick(Maybe<&2, Lex.Tok>, Bool.and(Calls.kind.oper(k), String.eq(o, "++")), lone.name(hh), None{})
    case Tree.Group{open, kids, close}:
      onto.call(hh, kids)
    case other:
      None{}

Uses (9):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool.and
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool.pick
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Maybe
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=String.eq
  https://jend.leeeet.dev/definition.txt?path=bolt@1.27.0.0/src/rules/calls.bend&name=kind.oper
  https://jend.leeeet.dev/definition.txt?path=bolt@1.27.0.0/src/rules/suspicious/concat.bend&name=lone.name
  https://jend.leeeet.dev/definition.txt?path=bolt@1.27.0.0/src/rules/suspicious/concat.bend&name=onto.call
  https://jend.leeeet.dev/definition.txt?path=bolt@1.27.0.0/src/syntax/lex.bend&name=Tok
  https://jend.leeeet.dev/definition.txt?path=bolt@1.27.0.0/src/syntax/tree.bend&name=Node