Add package core:flags

core/flags/example/example.odin

@@ -0,0 +1,132 @@
+package core_flags_example
+
+import "base:runtime"
+import "core:flags"
+import "core:fmt"
+import "core:net"
+import "core:os"
+import "core:time/datetime"
+
+
+Fixed_Point1_1 :: struct {
+	integer: u8,
+	fractional: u8,
+}
+
+Optimization_Level :: enum {
+	Slow,
+	Fast,
+	Warp_Speed,
+	Ludicrous_Speed,
+}
+
+// It's simple but powerful.
+my_custom_type_setter :: proc(
+	data: rawptr,
+	data_type: typeid,
+	unparsed_value: string,
+	args_tag: string,
+) -> (
+	error: string,
+	handled: bool,
+	alloc_error: runtime.Allocator_Error,
+) {
+	if data_type == Fixed_Point1_1 {
+		handled = true
+		ptr := cast(^Fixed_Point1_1)data
+
+		// precision := flags.get_subtag(args_tag, "precision")
+
+		if len(unparsed_value) == 3 {
+			ptr.integer = unparsed_value[0] - '0'
+			ptr.fractional = unparsed_value[2] - '0'
+		} else {
+			error = "Incorrect format. Must be in the form of `i.f`."
+		}
+
+		// Perform sanity checking here in the type parsing phase.
+		//
+		// The validation phase is flag-specific.
+		if !(0 <= ptr.integer && ptr.integer < 10) || !(0 <= ptr.fractional && ptr.fractional < 10) {
+			error = "Incorrect format. Must be between `0.0` and `9.9`."
+		}
+	}
+
+	return
+}
+
+my_custom_flag_checker :: proc(
+	model: rawptr,
+	name: string,
+	value: any,
+	args_tag: string,
+) -> (error: string) {
+	if name == "iterations" {
+		v := value.(int)
+		if !(1 <= v && v < 5) {
+			error = "Iterations only supports 1 ..< 5."
+		}
+	}
+
+	return
+}
+
+Distinct_Int :: distinct int
+
+main :: proc() {
+	Options :: struct {
+
+		file: os.Handle `args:"pos=0,required,file=r" usage:"Input file."`,
+		output: os.Handle `args:"pos=1,file=cw" usage:"Output file."`,
+
+		hub: net.Host_Or_Endpoint `usage:"Internet address to contact for updates."`,
+		schedule: datetime.DateTime `usage:"Launch tasks at this time."`,
+
+		opt: Optimization_Level `usage:"Optimization level."`,
+		todo: [dynamic]string `usage:"Todo items."`,
+
+		accuracy: Fixed_Point1_1 `args:"required" usage:"Lenience in FLOP calculations."`,
+		iterations: int `usage:"Run this many times."`,
+
+		// Note how the parser will transform this flag's name into `special-int`.
+		special_int: Distinct_Int `args:"indistinct" usage:"Able to set distinct types."`,
+
+		quat: quaternion256,
+
+		bits: bit_set[0..<8],
+
+		// Many different requirement styles:
+
+		// gadgets: [dynamic]string `args:"required=1" usage:"gadgets"`,
+		// widgets: [dynamic]string `args:"required=<3" usage:"widgets"`,
+		// foos: [dynamic]string `args:"required=2<4"`,
+		// bars: [dynamic]string `args:"required=3<4"`,
+		// bots: [dynamic]string `args:"required"`,
+
+		// (Maps) Only available in Odin style:
+
+		// assignments: map[string]u8 `args:"name=assign" usage:"Number of jobs per worker."`,
+
+		// (Variadic) Only available in UNIX style:
+
+		// bots: [dynamic]string `args:"variadic=2,required"`,
+
+		verbose: bool `usage:"Show verbose output."`,
+		debug: bool `args:"hidden" usage:"print debug info"`,
+
+		varg: [dynamic]string `usage:"Any extra arguments go here."`,
+	}
+
+	opt: Options
+	style : flags.Parsing_Style = .Odin
+
+	flags.register_type_setter(my_custom_type_setter)
+	flags.register_flag_checker(my_custom_flag_checker)
+	flags.parse_or_exit(&opt, os.args, style)
+
+	fmt.printfln("%#v", opt)
+
+	if opt.output != 0 {
+		os.write_string(opt.output, "Hellope!\n")
+	}
+}