049 parser runtime

// Test: Parser as runtime library
// Parses Koru source code and inspects the AST at runtime
// This proves the parser is fully usable as a library!

~import std/parser

const std = @import("std");

// Sample Koru code to parse
const SAMPLE_CODE =
    \\~event greet { name: []const u8 }
    \\| greeted
    \\
    \\~proc greet {
    \\    return .{ .greeted = .{} };
    \\}
;

// Event to inspect AST - using module:Type syntax!
~event inspect-ast { result: std.parser:ParseResult }

~proc inspect-ast|zig {
    std.debug.print("Parsed {} items\n", .{result.source_file.items.len});

    for (result.source_file.items) |item| {
        switch (item) {
            .event_decl => |event| {
                std.debug.print("Found event: ", .{});
                for (event.path.segments) |seg| {
                    std.debug.print("{s}", .{seg});
                }
                std.debug.print("\n", .{});
            },
            .proc_decl => |proc_decl| {
                std.debug.print("Found proc: ", .{});
                for (proc_decl.path.segments) |seg| {
                    std.debug.print("{s}", .{seg});
                }
                std.debug.print("\n", .{});
            },
            else => {},
        }
    }
}

// Event to report error - returns done when complete
~event report-error { message: []const u8 }

~proc report-error|zig {
    std.debug.print("Parse error: {s}\n", .{message});
}

// Modern Koru: proc = flow composition
~std/parser:parse.source(source: SAMPLE_CODE, file_name: "sample.kz", allocator: std.heap.page_allocator)
| parsed p |> inspect-ast(result: p)
| parse-error err |> report-error(message: err)