PEGO
G140: Typed Local Cuts
Ordinary typed rules with cuts can retain direct Go-local captures instead of falling back to general expression methods.
Mechanism and Invariants
Lexical cut flags preserve the surrounding choice/repetition scope. Marks restore input, environment, captures and recovered errors; cuts inside lookahead disappear on reset. Unsupported layouts and recovery bodies keep their own route.
Scope and State
Applied by default only to eligible generated typed Go bodies. Node parsing/recognition, closure, VMs and TypeScript retain their separate routes.
Reference Control
No generation option selects an alternative for this mechanism. Typed Go
output comes from the Flow IR printer, and its generated parsers are compared
with the engine oracle in the internal/engine tests.
Evidence and Implementation
Record 078 uses five same-generator direct/general pairs. For 512 rows, median ratios are 0.562 CodePoints and 0.712 Bytes, with unchanged allocation counts. Two-row gains are smaller. Both-unit result/error parity holds. The control removes the ordinary cut-bearing body group, not individual flags or later LR/Operators Rule cut extensions.
Evidence records: 078.
Source owners: typed structural emitter, framed body emission.
The comparison policy distinguishes same-source controls, historical changes and full checkpoints.