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+//
+// ------------------------------------------------------------
+// TOP SECRET TOP SECRET TOP SECRET TOP SECRET TOP SECRET
+// ------------------------------------------------------------
+//
+// Are you ready for the THE TRUTH about Zig string literals?
+//
+// Here it is:
+//
+// @TypeOf("foo") == *const [3:0]u8
+//
+// Which means a string literal is a "constant pointer to a
+// zero-terminated (null-terminated) fixed-size array of u8".
+//
+// Now you know. You've earned it. Welcome to the secret club!
+//
+// ------------------------------------------------------------
+//
+// Why do we bother using a zero/null sentinel to terminate
+// strings in Zig when we already have a known length?
+//
+// Versatility! Zig strings are compatible with C strings (which
+// are null-terminated) AND can be coerced to a variety of other
+// Zig types:
+//
+// const a: [5]u8 = "array".*;
+// const b: *const [16]u8 = "pointer to array";
+// const c: []const u8 = "slice";
+// const d: [:0]const u8 = "slice with sentinel";
+// const e: [*:0]const u8 = "many-item pointer with sentinel";
+// const f: [*]const u8 = "many-item pointer";
+//
+// All but 'f' may be printed. (A many-item pointer without a
+// sentinel is not safe to print because we don't know where it
+// ends!)
+//
+const print = @import("std").debug.print;
+
+const WeirdContainer = struct {
+ data: [*]const u8,
+ length: usize,
+};
+
+pub fn main() void {
+ // WeirdContainer is an awkward way to house a string.
+ //
+ // Being a many-item pointer (with no sentinel termination),
+ // the 'data' field "loses" the length information AND the
+ // sentinel termination of the string literal "Weird Data!".
+ //
+ // Luckily, the 'length' field makes it possible to still
+ // work with this value.
+ const foo = WeirdContainer {
+ .data = "Weird Data!",
+ .length = 11,
+ };
+
+ // How do we get a printable value from 'foo'? One way is to
+ // turn it into something with a known length. We do have a
+ // length... You've actually solved this problem before!
+ //
+ // Here's a big hint: do you remember how to take a slice?
+ const printable = ???;
+
+ print("{s}\n", .{printable});
+}