F＃中嵌套循环

语法

嵌套for循环语句的语法如下 

for var1 = start-expr1 to end-expr1 do
   for var2 = start-expr2 to end-expr2 do
      ... // loop body

while test-expression1 do
   while test-expression2 do
      body-expression

实例

let main() =
   for i = 1 to 5 do
      printf "\n"
      for j = 1 to 3 do
         printf "*"
main()

当编译和执行程序时，将产生以下输出 

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