Re^3: create hash names dynamically


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Re^3: create hash names dynamically

by Util (Priest)

on Jun 11, 2007 at 12:49 UTC ( [id://620489]=note: print w/replies, xml )

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in reply to Re^2: create hash names dynamically
in thread create hash names dynamically

This code:

foreach (1..3) {
  push @hashes, {};
}
[download]

does the same thing (but faster and cleaner) as this code:

foreach (1..3) {
  my %any_name;
  push @hashes, \%any_name;
}
[download]

At the end of the each loop in the second example, the %any_name hash would normally vanish, but because a *reference* to it is saved, the hash itself still floats in memory, with no name associated with it. Since a reference is a kind of scalar, it can be stored in the array just like any other scalar. The anonymous hash constructor, {}, allows you to avoid any %temp_hash that you did not need to refer to by name.

See also: