// Session 76 — `$x:tt` accepts any single call-site AST fragment
// (expr, literal, ident, block, stmt wrapper, …). Broader than `:expr`.
import Std::Io::{PrintLine, PrintInt};
import Std::Test::{Test_Pass};

// id_tt already existed in macro_repeat; here we also wrap blocks and stmts.
macro! id_tt {
    ( $x:tt ) => { $x }
}

macro! wrap_tt {
    ( $x:tt ) => {
        let v: int = $x;
        v + 1
    }
}

// stmt fragment via tt (call site parses `let …` as MacroStmt when using stmt kind;
// with tt, expression form still works: wrap values)
macro! twice_tt {
    ( $x:tt ) => { $x + $x }
}

func Main() -> int {
    let a: int = id_tt!(21);
    PrintInt(a);
    PrintLine("");
    let b: int = wrap_tt!(10);
    PrintInt(b);
    PrintLine("");
    let c: int = twice_tt!(3 + 4);
    PrintInt(c);
    PrintLine("");
    let d: int = id_tt!({ 1 + 2 });
    PrintInt(d);
    PrintLine("");
    if a != 21 || b != 11 || c != 14 || d != 3 {
        PrintLine("FAIL macro_tt");
        return 1;
    }
    PrintLine("PASS macro_tt");
    Test_Pass("macro_tt");
    return 0;
}