✓
Passing This code compiles and runs correctly.
Code
// Pins annotation entries as EXPRESSIONS over the compiler context: the
// entry `build == "release"` is a comparison evaluated against the compiler
// context (the --build flag provides the `build` binding), not an opaque
// word string-matched against the flag list. Pipe stays a list delimiter;
// logic lives INSIDE an entry, owned by its author; the consumer (here the
// import gate) decides which entries to honor.
//
// The imported module registers a tap, so the import is load-bearing: the
// [TAP] line in the output IS the expression evaluating true. Run with
// --build=release (COMPILER_FLAGS), so the gate must KEEP the import.
const std = @import("std");
~[build == "release"]import app/test_lib/tracer
~tor compute { x: i32 } -> i32
~proc compute|zig {
std.debug.print("compute({d})\n", .{x});
return x * 2;
}
~tor display { value: i32 }
~proc display|zig {
std.debug.print("Final: {d}\n", .{value});
}
~compute(x: 21): r |> display(value: r)
Supporting Files
~proc compute|cs {
__koru_stdout_write($"compute({x})\n");
return x * 2;
}
~proc display|cs {
__koru_stdout_write($"Final: {value}\n");
}~proc log|cs {
__koru_stdout_write($"[TAP] {event_name}\n");
}// JavaScript implementation facet. The Koru declarations live in the
// `tracer.kz` companion (merged at import); this file holds the `|js`
// proc bodies mirroring its `|zig` ones.
~proc log|js {
console.log(`[TAP] ${event_name}`);
}
// Tap module — importing it is what wires the tap (the 310_001 mechanism).
// The pin's gated import makes that wiring conditional: this module's output
// appears exactly when the import survives the annotation gate.
const std = @import("std");
~import std/taps
~pub tor log { event_name: string }
~proc log|zig {
std.debug.print("[TAP] {s}\n", .{event_name});
}
// compute is a bare-return `-> T` event, so the tap binds the produced value
// with `: r` (call-site bind rule, Lars-ruled 2026-06-25; 310_001 is the green
// precedent) — a branch tap has no named branch to match on a bare return.
~tap(input:compute -> input:display): r |> log(event_name: "compute")
Actual
compute(21)
[TAP] compute
Final: 42
Expected output
✓ Zig✓ C#compute(21)
[TAP] compute
Final: 42
Emitted Zig source
// Access compiler flags via the per-user compiler_env module
const CompilerEnv = @import("compiler_env").CompilerEnv;
pub const panic = if (@import("builtin").mode == .Debug)
@import("std").debug.FullPanic(@import("std").debug.defaultPanic)
else
@import("std").debug.simple_panic;
const __koru_bare = struct {
extern fn posix_memalign(memptr: *?*anyopaque, alignment: usize, size: usize) c_int;
extern fn free(ptr: ?*anyopaque) void;
fn bareAlloc(_: *anyopaque, len: usize, alignment: @import("std").mem.Alignment, _: usize) ?[*]u8 {
var p: ?*anyopaque = null;
const a = @max(alignment.toByteUnits(), @sizeOf(usize));
if (posix_memalign(&p, a, len) != 0) return null;
return @ptrCast(p);
}
fn bareResize(_: *anyopaque, _: []u8, _: @import("std").mem.Alignment, _: usize, _: usize) bool { return false; }
fn bareRemap(_: *anyopaque, _: []u8, _: @import("std").mem.Alignment, _: usize, _: usize) ?[*]u8 { return null; }
fn bareFree(_: *anyopaque, memory: []u8, _: @import("std").mem.Alignment, _: usize) void { free(@ptrCast(memory.ptr)); }
const vtable = @import("std").mem.Allocator.VTable{ .alloc = bareAlloc, .resize = bareResize, .remap = bareRemap, .free = bareFree };
const allocator = @import("std").mem.Allocator{ .ptr = undefined, .vtable = &vtable };
};
const __koru_backing = if (@import("builtin").link_libc) @import("std").heap.c_allocator else if (@import("builtin").os.tag == .freestanding) __koru_bare.allocator else @import("std").heap.page_allocator;
var __koru_leak_count: @import("std").atomic.Value(usize) = .init(0);
fn __koru_alloc(ctx: *anyopaque, len: usize, alignment: @import("std").mem.Alignment, ret_addr: usize) ?[*]u8 {
_ = ctx;
const r = __koru_backing.rawAlloc(len, alignment, ret_addr);
if (comptime @import("builtin").mode == .Debug) {
if (r != null) _ = __koru_leak_count.fetchAdd(1, .monotonic);
}
return r;
}
fn __koru_resize(ctx: *anyopaque, memory: []u8, alignment: @import("std").mem.Alignment, new_len: usize, ret_addr: usize) bool {
_ = ctx;
return __koru_backing.rawResize(memory, alignment, new_len, ret_addr);
}
fn __koru_remap(ctx: *anyopaque, memory: []u8, alignment: @import("std").mem.Alignment, new_len: usize, ret_addr: usize) ?[*]u8 {
_ = ctx;
return __koru_backing.rawRemap(memory, alignment, new_len, ret_addr);
}
fn __koru_free(ctx: *anyopaque, memory: []u8, alignment: @import("std").mem.Alignment, ret_addr: usize) void {
_ = ctx;
__koru_backing.rawFree(memory, alignment, ret_addr);
if (comptime @import("builtin").mode == .Debug) {
_ = __koru_leak_count.fetchSub(1, .monotonic);
}
}
const __koru_vtable = @import("std").mem.Allocator.VTable{ .alloc = __koru_alloc, .resize = __koru_resize, .remap = __koru_remap, .free = __koru_free };
pub fn koru_allocator() @import("std").mem.Allocator {
return .{ .ptr = undefined, .vtable = &__koru_vtable };
}
pub inline fn __koru_intcast(comptime T: type, x: anytype) T {
if (comptime (@import("builtin").mode == .Debug or @import("builtin").mode == .ReleaseSafe))
return @as(T, @intCast(x));
const dst = @typeInfo(T);
const src = @typeInfo(@TypeOf(x));
if (comptime (dst == .int and src == .int and dst.int.bits == src.int.bits and dst.int.signedness != src.int.signedness))
return @as(T, @bitCast(x));
return @as(T, @intCast(x));
}
pub fn koru_leak_check() void {
if (comptime @import("builtin").mode != .Debug) return;
if (__koru_leak_count.load(.acquire) == 0) return;
if (comptime @import("builtin").target.os.tag == .freestanding) {
if (comptime @import("builtin").cpu.arch == .wasm32 or @import("builtin").cpu.arch == .wasm64) {
@panic("KORU LEAK CHECK FAILED: the produced program leaked");
} else {
const __klc = struct { extern var stdout: ?*anyopaque; extern fn fputs(__s: [*:0]const u8, __st: ?*anyopaque) c_int; };
var __lb: [128]u8 = undefined;
const __lm = "KORU LEAK CHECK FAILED: allocations still outstanding at end of run: ";
@memcpy(__lb[0..__lm.len], __lm);
var __ln: usize = __lm.len;
var __lv = __koru_leak_count.load(.acquire);
var __ld: [20]u8 = undefined;
var __lk: usize = 0;
while (__lv > 0) : (__lk += 1) { __ld[__lk] = @intCast('0' + __lv % 10); __lv /= 10; }
for (0..__lk) |__li| { __lb[__ln] = __ld[__lk - 1 - __li]; __ln += 1; }
__lb[__ln] = '\n'; __ln += 1; __lb[__ln] = 0;
_ = __klc.fputs(@as([*:0]const u8, @ptrCast(&__lb)), __klc.stdout);
@trap();
}
} else {
@import("std").debug.print("KORU LEAK CHECK FAILED: the produced program leaked (trace above)\n", .{});
@import("std").process.exit(1);
}
}
pub const main_module = struct {
const std = @import("std");
pub const compute_event = struct {
pub const Input = struct {
x: i32,
};
pub const Output = i32;
pub inline fn handler(__koru_event_input: @This().Input) @This().Output {
return __koru_handler_impl(__koru_event_input.x);
}
fn __koru_handler_impl(__koru_p_0: i32) @This().Output {
const __koru_event_input: @This().Input = .{ .x = __koru_p_0 };
// >>> PROC: compute [tests/regression/300_ADVANCED_FEATURES/310_COMPTIME/310_105_conditional_import_expression_entry/input.kz:19]
const x = __koru_event_input.x;
_ = &x;
_ = &__koru_event_input;
std.debug.print("compute({d})\n", .{x});
return x * 2;
}
};
pub const display_event = struct {
pub const Input = struct {
value: i32,
};
pub const Output = void;
pub inline fn handler(__koru_event_input: @This().Input) @This().Output {
return __koru_handler_impl(__koru_event_input.value);
}
fn __koru_handler_impl(__koru_p_0: i32) @This().Output {
const __koru_event_input: @This().Input = .{ .value = __koru_p_0 };
// >>> PROC: display [tests/regression/300_ADVANCED_FEATURES/310_COMPTIME/310_105_conditional_import_expression_entry/input.kz:26]
const value = __koru_event_input.value;
_ = &value;
_ = &__koru_event_input;
std.debug.print("Final: {d}\n", .{value});
}
};
// >>> FLOW: tests/regression/300_ADVANCED_FEATURES/310_COMPTIME/310_105_conditional_import_expression_entry/input.kz:30 ~input:compute()
pub fn flow0() void {
const r = main_module.compute_event.handler(.{ .x = 21 });
const result_1 = koru_app.koru_test_lib.koru_tracer.log_event.handler(.{ .event_name = "compute" });
_ = &result_1;
_ = main_module.display_event.handler(.{ .value = r });
}
pub fn koru_start_flow() void {
const result_0 = koru_koru.start_event.handler(.{ });
const result_0_done = result_0.done;
_ = &result_0_done;
}
pub fn koru_end_flow() void {
const result_0 = koru_koru.end_event.handler(.{ });
const result_0_done = result_0.done;
_ = &result_0_done;
}
};
pub const koru_app = struct {
pub const koru_test_lib = struct {
pub const koru_tracer = struct {
const std = @import("std");
pub const log_event = struct {
pub const Input = struct {
event_name: []const u8,
};
pub const Output = void;
pub fn handler(__koru_event_input: @This().Input) @This().Output {
// >>> PROC: log [/Users/larsde/src/koru/tests/regression/300_ADVANCED_FEATURES/310_COMPTIME/310_105_conditional_import_expression_entry/test_lib/tracer.kz:10]
const event_name = __koru_event_input.event_name;
_ = &event_name;
_ = &__koru_event_input;
std.debug.print("[TAP] {s}\n", .{event_name});
}
};
};
};
};
pub const koru_koru = struct {
pub const start_event = struct {
pub const Input = struct {
};
pub const Output = union(enum(u8)) {
done: struct {
},
};
pub fn handler(__koru_event_input: @This().Input) @This().Output {
_ = &__koru_event_input;
return .{ .done = .{} };
}
};
pub const end_event = struct {
pub const Input = struct {
};
pub const Output = union(enum(u8)) {
done: struct {
},
};
pub fn handler(__koru_event_input: @This().Input) @This().Output {
_ = &__koru_event_input;
return .{ .done = .{} };
}
};
};
pub fn main() void {
main_module.koru_start_flow();
main_module.flow0();
main_module.koru_end_flow();
if (comptime @import("builtin").mode == .Debug) koru_leak_check();
}
test {
@import("std").testing.refAllDeclsRecursive(@This());
}
Emitted C# source
static class main_module {
public static void __koru_stdout_write(dynamic s) => global::System.Console.Out.Write(s);
public static void __koru_stderr_write(dynamic s) => global::System.Console.Error.Write(s);
// The mutable handle carrier — `*String`-style resources are
// `new __KoruBox { data = … }` because C# anonymous types are
// read-only: `s.data = …` (std/string append/clear, handle
// mutation generally) needs a settable member.
public class __KoruBox { public dynamic data; }
// Textification for `{{ … }}` operands: C# bool ToStrings as
// `True` where Koru prints `true`, and the operand's static type
// is unknown at this boundary — a `(x) is bool` inline test would
// be a compile error on statically-typed operands instead. Generic
// on purpose: `dynamic` boxed every value-type operand — measured
// ~1s/10M elements on 012_threat_scanner — while T specializes to
// the operand's own ToString() with no box.
public static string __koru_str<T>(T v) => v is bool b ? (b ? "true" : "false") : v?.ToString();
public static class compute_event {
public struct Input {
public int x;
}
public static int handler(Input __koru_input) {
var x = __koru_input.x;
__koru_stdout_write($"compute({x})\n");
return x * 2;
return default;
}
}
public static class display_event {
public struct Input {
public int value;
}
public static dynamic handler(Input __koru_input) {
var value = __koru_input.value;
__koru_stdout_write($"Final: {value}\n");
return default;
}
}
public static class app_test_lib_tracer_log_event {
public struct Input {
public string event_name;
}
public static dynamic handler(Input __koru_input) {
var event_name = __koru_input.event_name;
__koru_stdout_write($"[TAP] {event_name}\n");
return default;
}
}
public static class koru_start_event {
public struct Input {
}
public struct Output {
public string tag;
public dynamic done;
}
public static Output handler(Input __koru_input) => new Output { tag = "done" };
}
public static class koru_end_event {
public struct Input {
}
public struct Output {
public string tag;
public dynamic done;
}
public static Output handler(Input __koru_input) => new Output { tag = "done" };
}
public static void flow0() {
var r = main_module.compute_event.handler(new compute_event.Input { x = (int)(21)});
{
var __koru_p_event_name = (string)("compute");
__koru_stdout_write($"[TAP] {__koru_p_event_name}\n");
}
{
var __koru_p_value = (int)(r);
__koru_stdout_write($"Final: {__koru_p_value}\n");
}
}
public static void flow1() {
main_module.koru_start_event.handler(new koru_start_event.Input { });
}
public static void flow2() {
main_module.koru_end_event.handler(new koru_end_event.Input { });
}
}
static class Program {
static void Main() {
main_module.flow1();
main_module.flow0();
main_module.flow2();
}
}
Flows
flow ~compute click a branch to expand · @labels scroll to their anchor
compute (x: 21)
Test Configuration
MUST_RUN LANGUAGES: zig cs
Compiler Flags:
--build=release