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Advanced Perl Programming

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Previous: B.8 Meta-InformationAppendix B
Syntax Summary
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B.9 Typeglobs

  1. Typeglobs assignment aliases identifiers. In the following example, all identifiers named a (scalar, array, hash, subroutine, filehandle, format) are also available as b:

    *a = *b ;     # Alias
    $b = 10;      # Same as modifying $a
    b();          # Same as calling a()
  2. Selective aliasing:

    *a = \$b ;    # Only $a aliased to $b
  3. Constants:

    *a = \10;     # Alias a typeglob to a reference to a constant
    $a = 20;      # Run-time error - "Attempt to modify read-only variable"


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