How can I substitute an array for macro like keyword in Perl?

I am defining a lot of arrays of structs in a module. e.g.

my $array = [
   {
      Field1 => "FieldValue1"
   },
   {
      #etc...
   },
];
my $array2 = [
   {
      Field1 => "FieldValue1"
   },
   {
      #etc...
   },
];

I often repeat sequences of st开发者_StackOverflow社区ructs. For instance I might have five { Field1 => "FieldValue1" } structs in a row. Is it possible to save the sequence of structs in some data structure and insert that into my arrays?

e.g.

my $array3 = [ $Field1, $Field1, $Field1 ]; # $Field1 is a sequence of structs

You can do that but they will all wind up copies of each other. So editing the first one will change all of them. Instead use map.

my $array3 = [ map {Field1 => "FieldValue1"}, 1..5 ];

Any time that you find yourself repeating boilerplate code, Perl usually has a way around it.

I am not entirely clear what you want to do, but you could do something like this:

sub make_struct {
    {Field1 => "FieldValue1"}
}

my $array = [map make_struct, 1 .. 10];  # array with 10 hashes

sub make_struct_array {[map make_struct, 1 .. $_[0]]}

my $array2 = make_struct_array 20;  # array with 20 hashes

So in other words, write a subroutine that returns a new data structure for you. The subroutine can take a variety of options if you need to customize the structure.

The answers above work well for their own purposes, but they were not exactly what I wanted.

I ended up usin push() to create the arrays. $templatearray1 and $templatearray2 are arrays of structs. Push()'s behavior is to not insert the array reference. Instead it inserts the elements of the arrays. e.g.

my $myarray = [];
push(@$myarray, @$templatearray1);
push(@$myarray, @$templatearray2);
push(@$myarray, @$templatearray1);
push(@$myarray, @$templatearray2);
push(@$myarray, @$templatearray1);
push(@$myarray, @$templatearray2);
push(@$myarray, (
   {
      key1 => 'blah1',
      key2 => 'blah2',
   },
));