zig/src-self-hosted/TypedValue.zig

const std = @import("std");
const Type = @import("type.zig").Type;
const Value = @import("value.zig").Value;
const Allocator = std.mem.Allocator;
const TypedValue = @This();

ty: Type,
val: Value,

/// Memory management for TypedValue. The main purpose of this type
/// is to be small and have a deinit() function to free associated resources.
pub const Managed = struct {
    /// If the tag value is less than Tag.no_payload_count, then no pointer
    /// dereference is needed.
    typed_value: TypedValue,
    /// If this is `null` then there is no memory management needed.
    arena: ?*std.heap.ArenaAllocator.State = null,

    pub fn deinit(self: *Managed, allocator: *Allocator) void {
        if (self.arena) |a| a.promote(allocator).deinit();
        self.* = undefined;
    }
};