Zig-cli: now supports binding to struct fields

I am happy to share that I have finally merged a PR to make zig-cli to bind command line options to struct fields. Before this PR zig-cli only supported i64, f64, []const u8, and bool.

pub const OptionValue = union(enum) {
    bool: bool,
    string: ?[]const u8,
    int: ?i64,
    float: ?f64,
    string_list: ?[]const []const u8,

After this merge, option values are bound to some value:

var config = struct {
    host: []const u8 = "localhost",
    port: u16 = undefined,
var host = cli.Option{
    .long_name = "host",
    .help = "host to listen on",
    .value_ref = cli.mkRef(&config.host),
var port = cli.Option{
    .long_name = "port",
    .help = "port to bind to",
    .required = true,
    .value_ref = cli.mkRef(&config.port),

This approach has a few advantages:

  • It separates the value used by the CLI tool from the CLI user interface configuration.
  • It simplifies access to the provided command line options.
  • It enables support for arbitrary option types, e.g. IP address, etc.
  • It enables support for custom types.

The last two points are WIP.