d/demo/demo_std.d · 3841 字节 · 下载原文

// demo_std.d —— **标准输出**示范（D）

// demo_std.d —— **standard output** demo (D)

//

// 四层示范的第一层：只用这门语言自己的标准输出，**不读输入、不画图、不弹窗**，

// The first of the four demo layers: use only this language's own standard output, **no reading input, no drawing, no dialogs**,

// 输出**逐字节确定**，能正常结束。

// with **byte-for-byte deterministic** output, finishing normally.

//

// ◆ 写法（D 前端的实测约束）

// ◆ How to write it (measured constraints of the D frontend)

//

//   · `writeln` 的实参之间**不加分隔符**（`writeln("n = ", 42)` → `n = 42`），

//   · `writeln` puts **no separator** between its arguments (`writeln("n = ", 42)` → `n = 42`),

//     所以间距要自己写进字符串里。

//     so the spacing has to be written into the strings yourself.

//   · D **没有 extern / asm** ⇒ 裸调 `ui_2d_rect(...)` 会被编成 `CALL func_ui_rect`，

//   · D **has no extern / asm** ⇒ a bare call to `ui_2d_rect(...)` compiles into `CALL func_ui_rect`,

//     靠链接器剥 `func_` 前缀解析到 `lib_vmlui_ui_rect`，不需要声明（见 `catch.d`）。

//     and the linker strips the `func_` prefix to resolve it to `lib_vmlui_ui_rect`; no declaration needed (see `catch.d`).

//   · 颜色写负数十进制 —— 词法器十进制专用，不认 `0x`（见 `catch.d` 文件头）。

//   · Colors are written as negative decimals —— the lexer is decimal-only and does not recognize `0x` (see the head of `catch.d`).

//   · `\x1b` 转义**本前端是解析的**（与 Rust/Go 相反），见 `demo_tty.d`。

//   · `\x1b` escapes **are parsed by this frontend** (unlike Rust/Go); see `demo_tty.d`.

//

// 跑法：命令行页输入  vml run examples/d/demo_std.d

// How to run: type this on the command-line page  vml run examples/d/demo_std.d


#include "../../../Lib/d/vml_ui.d"
void main() {
    int lang = ui_scr_get_language();
    writeln("=== Dolaima demo_std (D) ===");

    // ① 字符串

    // ① string

    if (lang == 0) { writeln("[字符串] hello, world"); } else { writeln("[string] hello, world"); }

    // ② 整数

    // ② integer

    int n = 42;
    if (lang == 0) { writeln("[整数] n = ", n); } else { writeln("[int] n = ", n); }

    // ③ 计算结果

    // ③ computed result

    if (lang == 0) { writeln("[计算] 6 * 7 = ", 6 * 7); } else { writeln("[calc] 6 * 7 = ", 6 * 7); }
    int a = 7;
    int b = 5;
    if (lang == 0) { writeln("[计算] a + b = ", a + b); } else { writeln("[calc] a + b = ", a + b); }
    if (lang == 0) { writeln("[计算] a * b - 3 = ", a * b - 3); } else { writeln("[calc] a * b - 3 = ", a * b - 3); }

    // ④ 循环里算斐波那契前 10 项

    // ④ compute the first 10 Fibonacci numbers in a loop

    if (lang == 0) { writeln("[循环] 斐波那契前 10 项："); } else { writeln("[loop] first 10 Fibonacci numbers:"); }
    int x = 0;
    int y = 1;
    int i = 0;
    while (i < 10) {
        int z = x + y;
        x = y;
        y = z;
        writeln("  fib = ", x);
        i = i + 1;
    }

    // ⑤ 累加 1+2+…+100

    // ⑤ sum 1+2+…+100

    int sum = 0;
    int k = 1;
    while (k <= 100) {
        sum = sum + k;
        k = k + 1;
    }
    if (lang == 0) { writeln("[累加] 1+2+...+100 = ", sum); } else { writeln("[sum] 1+2+...+100 = ", sum); }

    // ⑥ 阶乘 5!

    // ⑥ factorial 5!

    int fact = 1;
    int m = 1;
    while (m <= 5) {
        fact = fact * m;
        m = m + 1;
    }
    if (lang == 0) { writeln("[阶乘] 5! = ", fact); } else { writeln("[factorial] 5! = ", fact); }

    if (lang == 0) { writeln("=== 结束 ==="); } else { writeln("=== done ==="); }
}