SchemaFragments.merge: def of bendvy-ecs-core@0.1.0.3
Import: import bendvy-ecs-core@0.1.0.3/schema_fragments.bend as SchemaFragments
Lines 135-140 of bendvy-ecs-core@0.1.0.3/schema_fragments.bend: https://jend.leeeet.dev/read.txt?path=bendvy-ecs-core@0.1.0.3/schema_fragments.bend&start_line=135&end_line=140

import Base

# Validate both fragments and their combined entries before combining owners.
# Success retains left-then-right entries and (L & R) owners; refusal returns
# both original fragments. No initializer or gameplay callback is invoked.
def merge(~S: Data,~L: Type,~R: Type,left: Fragment<S,L>,right: Fragment<S,R>) -> Merge<S,L,R>:
  match left right:
    case Fragment{+le,l} Fragment{+re,r}: merge_checked(~S,~L,~R,first_failure(validate(~S,le),first_failure(validate(~S,re),validate(~S,List.append(&2,Entry<S>,le,re)))),List.append(&2,Entry<S>,le,re),Fragment{le,l},Fragment{re,r})

Uses (7):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List.append
  https://jend.leeeet.dev/definition.txt?path=bendvy-ecs-core@0.1.0.3/schema_fragments.bend&name=Entry
  https://jend.leeeet.dev/definition.txt?path=bendvy-ecs-core@0.1.0.3/schema_fragments.bend&name=Fragment
  https://jend.leeeet.dev/definition.txt?path=bendvy-ecs-core@0.1.0.3/schema_fragments.bend&name=Merge
  https://jend.leeeet.dev/definition.txt?path=bendvy-ecs-core@0.1.0.3/schema_fragments.bend&name=first_failure
  https://jend.leeeet.dev/definition.txt?path=bendvy-ecs-core@0.1.0.3/schema_fragments.bend&name=merge_checked
  https://jend.leeeet.dev/definition.txt?path=bendvy-ecs-core@0.1.0.3/schema_fragments.bend&name=validate