Result: done
Files: crates/nikaia-std/src/tools/check_core_args.nika crates/nikaia-std/src/tools/check_core_ops.nika crates/nikaia-std/src/tools/check_core_stmt.nika crates/nikaia-std/src/tools/check_facts.nika crates/nikaia-std/src/tools/check_flow.nika crates/nikaia-std/src/tools/emit_core_flow.nika crates/nikaia-std/src/tools/lowered.rs crates/nikaia-std/src/tools/lowered/check_core_args.rs crates/nikaia-std/src/tools/lowered/check_core_ops.rs crates/nikaia-std/src/tools/lowered/check_core_stmt.rs crates/nikaia-std/src/tools/lowered/check_facts.rs crates/nikaia-std/src/tools/lowered/check_flow.rs crates/nikaia-std/src/tools/lowered/emit_core_flow.rs tests/compiler/tests/let_lambda_string_param.nika tests/compiler/tests/let_lambda_string_param.stdout
Commit: check, emit: a let-bound lambda takes its parameter types from its first use
Body: A let lambda without a type whose parameters are untyped is now typed by the first call in the rest of its block that hands it to a parameter of fn type that runs it (as ADR-135 D2 types an empty list by its first use): the checker sets that type as the lambda’s expected one, so the body is checked as the same lambda written into the call (as_text, .copied()), records the parameter types (lambda_params_by_use) which the emitter writes on the closure (|n: String|), and treats the name as code run in place (run_code), so it is handed on as &w, not as a kept value. A callee that keeps the value is left as before (a kept lambda needs its type on the let). Separately, a lambda checked by check_core_ops_closure (a let-bound one, also with a declared type) now copies a map read that is its last value, as one handed to a call does (let v: fn(String) -> i64? sync = fn(n) { m.get(n) } missed .copied()).
Fixes: #997
Pushed: bad24d06 (pushed by drive.nika)
Tests: tests/compiler –both-settings 355/355 ok both (new let_lambda_string_param); rows 1-3 failed in rustc on the unfixed compiler (probes before the change: E0277 str Sized, Borrow
