Zig Result-Location-Semantics footgun

initialization_footgun.zig

const std = @import("std");

fn t1init(alloc: std.mem.Allocator, path1: []const u8) ![]const u8 {
    const stdout_wr = std.io.getStdOut().writer();
    try stdout_wr.writeAll("t1init"); // prevent compiler to optimize away this fn
    return try alloc.dupe(u8, path1);
}

fn t2init(alloc: std.mem.Allocator, path2: []const u8) ![]const u8 {
    _ = path2;
    _ = alloc;
    const stdout_wr = std.io.getStdOut().writer();
    try stdout_wr.writeAll("t2init"); // prevent compiler to optimize away this fn
    return error.fail2;
}

const ResStruct = struct {
    t1: []const u8,
    t2: []const u8,

    fn init(alloc: std.mem.Allocator, path: []const u8) !ResStruct {
        return .{
            .t1 = try t1init(alloc, path),
            .t2 = try t2init(alloc, path),
        };
    }
    fn deinit(self: *ResStruct, alloc: std.mem.Allocator) void {
        alloc.free(self.t1);
        alloc.free(self.t2);
    }
};

pub fn main() !void {
    var general_purpose_allocator = std.heap.GeneralPurposeAllocator(.{}){};
    defer std.debug.assert(!general_purpose_allocator.deinit());
    const gpa = general_purpose_allocator.allocator();
    var rest_struct = try ResStruct.init(gpa, "testme123");
    defer rest_struct.deinit(gpa);
}