FAQ: What are all these $@%&* punctuation signs, and how do I know when to use them?

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7.2: What are all these $@%&* punctuation signs, and how do I know when to use

    They are type specifiers, as detailed in the perldata manpage:

        $ for scalar values (number, string or reference)
        @ for arrays
        % for hashes (associative arrays)
        & for subroutines (aka functions, procedures, methods)
        * for all types of that symbol name.  In version 4 you used them like
          pointers, but in modern perls you can just use references.

    There are couple of other symbols that you're likely to encounter that
    aren't really type specifiers:

        <> are used for inputting a record from a filehandle.
        \  takes a reference to something.

    Note that <FILE> is *neither* the type specifier for files nor the name
    of the handle. It is the "<>" operator applied to the handle FILE. It
    reads one line (well, record--see the section on "$/" in the perlvar
    manpage) from the handle FILE in scalar context, or *all* lines in list
    context. When performing open, close, or any other operation besides
    "<>" on files, or even when talking about the handle, do *not* use the
    brackets. These are correct: "eof(FH)", "seek(FH, 0, 2)" and "copying
    from STDIN to FILE".


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