声明数据结构 包含复杂数据结构

870阅读　0评论2013-05-23　zhengsenlin888
分类：PERL


  1. #下面有4个例子，但通常最后一个更常用。
  2. my %owner1 = (
  3.     "name" => "Santa Claus",
  4.     "DOB" => "1882-12-25",
  5. );

  7. my $owner1Ref = %owner1;

  9. my %owner2 = (
  10.     "name" => "Mickey Mouse",
  11.     "DOB" => "1928-11-18",
  12. );

  14. my $owner2Ref = %owner2;

  16. my @owners = ( $owner1Ref, $owner2Ref );

  18. my $ownersRef = @owners;

  20. my %account = (
  21.     "number" => "12345678",
  22.     "opened" => "2000-01-01",
  23.     "owners" => $ownersRef,
  24. );

  1. #显然你不用这么费劲，可以简化为：
  2. my %owner1 = (
  3.     "name" => "Santa Claus",
  4.     "DOB" => "1882-12-25",
  5. );

  7. my %owner2 = (
  8.     "name" => "Mickey Mouse",
  9.     "DOB" => "1928-11-18",
  10. );

  12. my @owners = ( %owner1, %owner2 );

  14. my %account = (
  15.     "number" => "12345678",
  16.     "opened" => "2000-01-01",
  17.     "owners" => @owners,
  18. );


  1. #也可以使用不同的符号声明匿名数组和哈希表。匿名数组使用方括号，匿名哈希表使用大括号。 这样，返回值就是一个对匿名数据结构的引用。细看一下， 返回的 %accountas 与上面相同：
  2. # Braces denote an anonymous hash
  3. my $owner1Ref = {
  4.     "name" => "Santa Claus",
  5.     "DOB" => "1882-12-25",
  6. };

  8. my $owner2Ref = {
  9.     "name" => "Mickey Mouse",
  10.     "DOB" => "1928-11-18",
  11. };

  13. # Square brackets denote an anonymous array
  14. my $ownersRef = [ $owner1Ref, $owner2Ref ];

  16. my %account = (
  17.     "number" => "12345678",
  18.     "opened" => "2000-01-01",
  19.     "owners" => $ownersRef,
  20. );


  1. #或者更短一些（这就是真正用来声明复杂数据结构的形式）：
  2. my %account = (
  3.     "number" => "31415926",
  4.     "opened" => "3000-01-01",
  5.     "owners" => [
  6.         {
  7.             "name" => "Philip Fry",
  8.             "DOB" => "1974-08-06",
  9.         },
  10.         {
  11.             "name" => "Hubert Farnsworth",
  12.             "DOB" => "2841-04-09",
  13.         },
  14.     ],
  15. );


  1. say "$account{owners}[0]{ddddd}";
  2. say "$account{owners}[1]{aaaa}";
  3. say "$account{owners}->[0]->{ddddd}";
    say "$account{owners}->[1]->{aaaa}";


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