15 open tx auto close

✓ Passing This code compiles and runs correctly.

Code

// Ground truth for korulang.org phantom explorer — commit then auto-close.
// The committed <active!> connection is bound and discarded (`: _`); auto-
// discharge inserts close() on the dropped obligation, exactly as the old
// `| committed _ |> _` branch discard did — the migration is mechanical.
//
// EXPECTED: Compiles and runs successfully

import app/db

app/db:open(connstr: "postgres://localhost/test")
| connected c |> app/db:tx.begin(conn: c): t |> app/db:tx.exec(tx: t, sql: "INSERT INTO users VALUES (1, 'alice')"): r |> app/db:tx.commit(tx: r): _
| connection-failed |> _

input.k

Actual

Executing: INSERT INTO users VALUES (1, 'alice')
COMMIT
Connection closed

Expected output

Executing: INSERT INTO users VALUES (1, 'alice')
COMMIT
Connection closed

Flows

flow ~open click a branch to expand · @labels scroll to their anchor

open (connstr: "postgres://localhost/test")

Imported Files

// open/tx lifecycle API — ground truth for korulang.org phantom explorer

const std = @import("std");

const Connection = struct { handle: i32 };
const Transaction = struct { conn_handle: i32 };

~pub event open { connstr: []const u8 }
| connected *Connection<connected!>
| connection-failed

~proc open|zig {
    _ = connstr;
    const c = std.heap.page_allocator.create(Connection) catch unreachable;
    c.* = Connection{ .handle = 42 };
    return .{ .connected = c };
}

~pub event tx.begin { conn: *Connection<!connected|!active> } -> *Transaction<started!>

~proc tx.begin|zig {
    const t = std.heap.page_allocator.create(Transaction) catch unreachable;
    t.* = Transaction{ .conn_handle = conn.handle };
    return t;
}

~pub event tx.exec { tx: *Transaction<!started|!active>, sql: []const u8 } -> *Transaction<active!>

~proc tx.exec|zig {
    std.debug.print("Executing: {s}\n", .{sql});
    return tx;
}

~pub event tx.commit { tx: *Transaction<!active> } -> *Connection<active!>

~proc tx.commit|zig {
    std.debug.print("COMMIT\n", .{});
    const c = std.heap.page_allocator.create(Connection) catch unreachable;
    c.* = Connection{ .handle = tx.conn_handle };
    std.heap.page_allocator.destroy(tx);
    return c;
}

~pub event tx.rollback { tx: *Transaction<!active> } -> *Connection<active!>

~proc tx.rollback|zig {
    std.debug.print("ROLLBACK\n", .{});
    const c = std.heap.page_allocator.create(Connection) catch unreachable;
    c.* = Connection{ .handle = tx.conn_handle };
    std.heap.page_allocator.destroy(tx);
    return .{ .rolled_back = c };
}

~pub event close { conn: *Connection<!active> }

~proc close|zig {
    std.debug.print("Connection closed\n", .{});
    std.heap.page_allocator.destroy(conn);
}

db.kz

Test Configuration

MUST_RUN

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