parseBlockExprStatement

    pub fn parseBlockExprStatement(p: *Parser) Error!bool {
        const def_index = @backingInt(Def.defBlockExprStatement);
        if (p.depths[def_index] > max_depth) return error.MaxDepth;
        p.depths[def_index] += 1;
        defer p.depths[def_index] -= 1;
        return blk_0: {
            const pos_0 = p.i;
            if (try p.parseBlockExpr()) break :blk_0 true;
            p.i = pos_0;
            if (blk_1: {
                const pos_1 = p.i;
                const match_1 = try p.parseBlockExprPrefix();
                p.i = pos_1;
                break :blk_1 !match_1;
            } and try p.parseAssignExpr() and try p.parseSEMICOLON()) break :blk_0 true;
            p.i = pos_0;
            break :blk_0 false;
        };
    }