004 file processor

✓ Passing This code compiles and runs correctly.

Code

// Test 831: File processor (realistic I/O pattern with directory imports)
//
// Common pattern: read file -> process lines -> transform -> write output
// Tests: directory imports, multiple modules from same package, error handling

const std = @import("std");

// Import directory 'lib/io' containing:
// - file.kz (read, write events)
// - parse.kz (lines event)
// - transform.kz (uppercase event)
~import "$app/lib/io"

// The full pipeline using directory imports
~app.lib.io.file:read(path: "input.txt")
| success s |> app.lib.io.parse:lines(text: s.contents)
    | parsed |> app.lib.io.transform:uppercase(text: s.contents)
        | transformed t |> app.lib.io.file:write(path: "output.txt", data: t.result)
            | written |> _
            | ioerror |> _
| notfound |> _
| ioerror |> _

input.kz

Imported Files

// File I/O module

const std = @import("std");

~pub event read { path: []const u8 }
| success { contents: []const u8 }
| notfound {}
| ioerror { msg: []const u8 }

~pub event write { path: []const u8, data: []const u8 }
| written {}
| ioerror { msg: []const u8 }

~proc read {
    // Stub implementation for test
    return .{ .@"notfound" = .{} };
}

~proc write {
    // Stub implementation for test
    return .{ .@"ioerror" = .{ .msg = "write not implemented" } };
}

lib/io/file.kz

// Parse module

const std = @import("std");

~pub event lines { text: []const u8 }
| parsed { lines: [][]const u8 }

~proc lines {
    // Stub implementation for test
    const empty: [][]const u8 = &.{};
    return .{ .@"parsed" = .{ .lines = empty } };
}

lib/io/parse.kz

// Transform module

const std = @import("std");

~pub event uppercase { text: []const u8 }
| transformed { result: []const u8 }

~proc uppercase {
    // Stub implementation for test
    return .{ .@"transformed" = .{ .result = "" } };
}

lib/io/transform.kz

Test Configuration

Expected Behavior:

BACKEND_COMPILE_ERROR

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