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#define Perl:   \
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    yyy:
        // "93% of paint splatters are valid perl programs"
        https://www.mcmillen.dev/sigbovik/
        // note: if all man pages were as good as perl's, this document would be useless
        man 1 perl

    "One thing that distinguishes Perl\
     from other languages is its use of sigils;" - official documentation

    "There’s more than one way to do it." - motto

    • interpreted language
    • dynamic typing
    • legendary for being unreadable when written by monsters
    • sits somewhere between a shell with lots of builtins and python
    • very expressive
    • it is a better PHP; whatever you are doing with PHP, Perl could do it twice as well

    
        • concise
        • no odd restrictions on the syntax
        • hackable (in the MIT sense)
    
        • can become hard to read or maintain

    Files:
        .pl     : perl script
        .pod    : perl documentation file
        .tt     : perl::Template template file

    Programs:
        perl <script> <arguments>   : interpreter
        cpan                        : "Comprehensive Perl Archive Network"; dependency manager
        cpanp                       : "CPAN Plus"; unstable and bloated cpan alternative
        cpanm                       : "CPAN Minus"; minimalistic CPAN alternative
        reply                       : "REPL Yay"; repl for perl; from the package Reply
        perldoc                     : man like tool for perl documentation (see BELOW)

    Documentation:
        
            man 1 perldoc
        perdoc <module|subject>
        perdoc -f <function>
        • designed after man
        •  you are recommended to set ${PERLDOC_PAGER} to ${MANPAGER}
        POD:
            • "Plain Old Documentation"
            • roff like format with perl spicing
            • significantly more readable than roff

    Comments:
        # single line comment

    Semicolons:
        <statement>;
        • required (except after the last statement)

    Pragmas:
        use <pragma> // enables pragma
        no <pragma>  // disables pragma
        strict      : make some unsafe constructs into errors; generally recommended
        warnings    : report additional diagnostics

    Variables:
        my <sigil><name> [assignment]
        <sigil><name>
        •  the keyword "my" is only required with the strict pragma on
        sigil:
            • signals the type of value we are using
            $   : primitive or object
            @   : array
            %   : hash (map)
            &   : subroutine
            *   : type glob
        my $var;
my $number = 10;
my @array  = ($number, $number, $number);
my %map    = (ten => $number, also_ten => $number);


    Literals:
        String:
            "<...>"          : interpolating string
            '<...>'          : non-interpolating string
            <sigil><name>    : variable interpolation
            <sigil>{<name>}  : unambiguous variable interpolation
            — function call interpolation is not directly supported:
                • however array literals are expended and evaluated inside
                  unambiguous variable interpolation
                • this allows for the following trick
                print "@{ [time] }"
# Example Out: 1742495945
# (time is a builtin function that returns UNIX time)

        Misc:
            [<element*>]    : array
            (<element>*)    : map

    Functions:
        sub [name] { <...> }
        • "SUBroutine"
        • when a name is not specified, it acts as a lambda

    Replacing:
        s/<...>/<...>/<flag>*
        • sed. its literally inline sed

    Shells:
        `<command>`         : executes a command and returns its captured output
        qx<d><command><d>   : exactly like above, but could be easier to search for in the code
                               and you can choose your delimiter { "{}", "()" }
        system(<command>)   : execute a command and return its exit code;
                               the output of the command is appended to the processes output

    Regex:
        • Perl is famous for its great regular expression system
        • other languages often have libraries that implement Perl compatible regex-es,
          or "PCRE" as its commonly referred to

    Libraries:
        use <library>
        Template:
            use Template;
            
                perldoc Template
            — supports:
                • logic
                • loops
                • including
            • very versatile, can be used to preprocess just about anything
            • the syntax is clean and readable