fast-replacing-keeps-bindings-with-a-condition-and-empty-middle.yaml

# SPDX-FileCopyrightText: Copyright (c) 2025 Objectionary.com
# SPDX-License-Identifier: MIT
---
input: '[[ a -> [[ ]], b -> [[ ]] ]]'
output: '⟦ y ↦ ξ, a ↦ ⟦⟧, b ↦ ⟦⟧ ⟧'
rules:
  custom:
    - name: insert-y
      pattern: '[[ !B1, !B2 ]]'
      result: '[[ !B1, y -> $, !B2 ]]'
      when:
        eq: [1, 1]