swift/demo/demo_std.swift · 5123 字节 · 下载原文

// demo_std.swift —— **标准输出**示范（Swift）

// demo_std.swift — a **standard output** demo (Swift)

//

// 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**，

// Layer 1 of the four-layer demo: use only this language's own standard output, **no input reading, no drawing, no dialogs**,

// 输出**逐字节确定**，能正常结束。

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

//

// ◆ 写法（Swift 前端的实测约束）

// ◆ Style (measured constraints of the Swift frontend)

//

//   · `print` 多个实参之间**不加分隔符**（`print("n =", 7)` → `n =7`），

//   · `print` **adds no separator** between multiple arguments (`print("n =", 7)` → `n =7`),

//     所以间距要自己写进字符串里（`print("n = ", 7)` → `n = 7`）。

//     so the spacing must be written into the string yourself (`print("n = ", 7)` → `n = 7`).

//   · 没有 `str(x)` 这种整数转字符串的内置函数（写了报「未定义的函数 'str'」）⇒

//   · There is no `str(x)` builtin for int-to-string (writing one reports "undefined function 'str'") ⇒

//     要拼串得自己写 `numToStr`（见 `snake.swift`）；这一份把标签和值分开传，

//     to build strings you must write your own `numToStr` (see `snake.swift`); this copy passes the label and the value separately,

//     不需要转换。

//     so no conversion is needed.

//   · **状态放数组、常量放函数返回值** —— 这几门前端的模块级标量读出来是垃圾

//   · **State goes in arrays, constants in function return values** — module-level scalars read back as garbage in these frontends

//     （见 `snake.swift` 文件头）。这一份只用 `main` 里的局部量。

//     (see the header of `snake.swift`). This copy uses only locals inside `main`.

//   · `\u{1B}` 转义不支持；控制字符走 `putchar(码)`，见 `demo_tty.swift`。

//   · The `\u{1B}` escape is unsupported; control characters go through `putchar(code)`, see `demo_tty.swift`.

//     （✅ 2026-10-04 复验仍成立：实测 `"\u{1B}[31m"` 的 `.count` = 10 —— 整串按**字面**存下、转义没被解释。）

//     (✅ Re-checked 2026-10-04, still true: measured `"\u{1B}[31m"`.count == 10 -- the whole string is stored **literally**, the escape is not interpreted.)

//     （顺带量到 `"\n"` / `"\t"` 的 `.count` 也都是 2 ⇒ 本前端**任何**反斜杠转义都不解释。）

//     (Also: `"\n"` / `"\t"` both measure .count == 2 ⇒ this frontend interprets **no** backslash escape at all.)

//

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

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


// 界面语言：开局查一次（`ui_scr_get_language` 是 syscall，别每处都调）

// UI language: queried once at start (`ui_scr_get_language` is a syscall, do not call it everywhere)

#include "../../../Lib/swift/vml_ui.swift"
var lang = ui_scr_get_language()

// ⚠ 这里用**单行 `if/else`** 而不是三元 —— 本前端 `print(非字面量)` 打的是**指针**（实测），

// ⚠ A **one-line `if/else`** is used here instead of a ternary -- this frontend's `print(non-literal)` prints a **pointer** (measured),

//   只有**字面量**实参才真的打字符串；三元的写法留给 `print_str` / `ui_*`。

//   and only a **literal** argument really prints the string; the ternary form is left to `print_str` / `ui_*`.


print("=== Dolaima demo_std (Swift) ===")

// ① 字符串

// ① Strings

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

// ② 整数

// ② Integers

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

// ③ 计算结果

// ③ Computed results

if lang == 0 { print("[计算] 6 * 7 = ", 6 * 7) } else { print("[calc] 6 * 7 = ", 6 * 7) }
let a = 7
let b = 5
if lang == 0 { print("[计算] a + b = ", a + b) } else { print("[calc] a + b = ", a + b) }
if lang == 0 { print("[计算] a * b - 3 = ", a * b - 3) } else { print("[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 { print("[循环] 斐波那契前 10 项：") } else { print("[loop] first 10 Fibonacci numbers:") }
var x = 0
var y = 1
var i = 0
while i < 10 {
    var z = x + y
    x = y
    y = z
    print("  fib = ", x)
    i = i + 1
}

// ⑤ 累加 1+2+…+100

// ⑤ Sum 1+2+…+100

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

// ⑥ 阶乘 5!

// ⑥ Factorial 5!

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

if lang == 0 { print("=== 结束 ===") } else { print("=== end ===") }