# hello.nim
echo "Hello, World!"

nim c -r hello.nim

nim c hello.nim          # 仅编译，生成 hello（Linux）或 hello.exe（Windows）
nim c -r hello.nim       # 编译并运行
nim c -o:myapp hello.nim # 指定输出文件名

# 输出字符串
echo "Hello, Nim!"

# 输出数字
echo 42
echo 3.14

# 输出多个值（用逗号分隔）
echo "Name: ", "Nim", ", Version: ", NimVersion

# 输出表达式
echo "2 + 3 = ", 2 + 3

# 输出序列
echo @[1, 2, 3, 4, 5]

# 方法一：字符串拼接
let name = "Nim"
let version = 2
echo "Welcome to " & name & " " & $version & "!"

# 方法二：使用 & 格式化字符串（需要 import std/strformat）
import std/strformat

let pi = 3.14159
echo &"Pi is approximately {pi:.2f}"
# 输出: Pi is approximately 3.14

let items = 5
let price = 9.99
echo &"Total: {items} × ${price:.2f} = ${items.float * price:.2f}"
# 输出: Total: 5 × $9.99 = $49.95

# write 不换行，echo 换行
stdout.write "Hello, "
stdout.write "World!"
stdout.write "\n"

# writeLine 等同于 echo
stdout.writeLine "This is a line"

# 读取一行输入
echo "What is your name?"
let name = stdin.readLine()
echo "Hello, ", name, "!"

# 读取整数
echo "Enter a number:"
let num = parseInt(stdin.readLine())
echo "You entered: ", num

# 读取多个值
echo "Enter two numbers (space separated):"
let parts = stdin.readLine().split(" ")
let a = parseInt(parts[0])
let b = parseInt(parts[1])
echo &"{a} + {b} = {a + b}"

# 直接运行脚本
nim e hello.nims

# 或者给脚本添加执行权限
chmod +x hello.nims
./hello.nims

#!/usr/bin/env nim e
echo "Running as NimScript!"
echo "Nim version: ", NimVersion
echo "Current OS: ", hostOS

nimble init myproject

# This is just an example to get you started. A typical library package
# exports the main API in this file. Note that you cannot rename this file
# but you can remove it if you wish.

proc add*(x, y: int): int =
  ## Adds two numbers together.
  return x + y

when isMainModule:
  echo add(2, 3)

nim c main.nim
# 等同于
nim c --assertions:on --checks:on --hints:on main.nim

nim c -d:release main.nim

nim c -d:danger main.nim

# 根据操作系统选择不同行为
when defined(windows):
  echo "Running on Windows"
elif defined(linux):
  echo "Running on Linux"
elif defined(macosx):
  echo "Running on macOS"
else:
  echo "Unknown OS"

# 根据编译模式
when defined(release):
  echo "Release build"
else:
  echo "Debug build"

# 根据编译后端
when defined(js):
  proc alert(msg: string) {.importjs: "alert(#)".}
  alert("In JavaScript!")
else:
  echo "In native code!"

# 使用 -d 标志定义自定义符号
# 编译: nim c -d:verbose -d:version=2 main.nim

when defined(verbose):
  echo "Verbose mode enabled"

const Version {.intdefine.} = 1
echo "Version: ", Version

# 在命令行定义
# nim c -d:appName=MyApp main.nim

const appName {.strdefine.} = "DefaultApp"
echo "Running: ", appName

mkdir -p myapp/src/myapp
cd myapp
nimble init myapp -y

# src/myapp.nim
import myapp/[calculator, formatter]

when isMainModule:
  let result = add(10, 20)
  echo formatResult("Addition", 10, 20, result)
  
  let product = multiply(5, 6)
  echo formatResult("Multiplication", 5, 6, product)

# src/myapp/calculator.nim

proc add*(a, b: int): int =
  ## Add two integers
  return a + b

proc subtract*(a, b: int): int =
  ## Subtract b from a
  return a - b

proc multiply*(a, b: int): int =
  ## Multiply two integers
  return a * b

proc divide*(a, b: float): float =
  ## Divide a by b
  if b == 0:
    raise newException(DivByZeroDefect, "Cannot divide by zero")
  return a / b

# src/myapp/formatter.nim
import std/strformat

proc formatResult*(op: string, a, b, result: int): string =
  ## Format a calculation result as a string
  &"{op}: {a} and {b} = {result}"

proc formatCurrency*(amount: float, currency: string = "$"): string =
  ## Format a number as currency
  &"{currency}{amount:.2f}"

nim c -r src/myapp.nim

# 这是单行注释

#[这是
多行
注释]#

proc add*(a, b: int): int =
  ## 计算两个整数的和
  ## 
  ## .. code-block:: nim
  ##   echo add(1, 2)  # 输出 3
  return a + b

type
  User* = object
    ## 用户对象
    ## 
    ## 存储用户的基本信息
    name*: string  ## 用户名
    age*: int      ## 年龄

nim doc src/myapp.nim
# 生成 src/myapp.html

# 使用 -e 标志直接执行代码
nim e -e "echo 2 + 2"

# 使用 --eval 标志
nim --eval:"echo \"Hello\""

# 查看生成的 C 代码
nim c --genScript main.nim
cat nimcache/main.c

# 为 Linux ARM64 编译
nim c --os:linux --cpu:arm64 main.nim

# 为 Windows 编译
nim c --os:windows --cpu:amd64 main.nim