BEGIN { require Module; import Module LIST; }
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Generally I would always use use even if you don't export any symbols.

One place where require would be preferred over use is when you want to include a module only when it really is needed. So you'll see code like:

if ($type eq "Excel file") {
  require SpreadsheetReader::Excel;
  my $parser = SpreadsheetReader::Excel->new();
  ...
}
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use Module LIST is equivalent to: BEGIN { require Module; import Module LIST; }

Nit: it's actually equivalent to:

BEGIN { require Module; Module->import( LIST ); }

use always performs a method call, where the indirect invocation form you had sometimes does not perform a method call. (If you want to be very specific, it's probably closer to Module::->import( LIST ), but you have to read the code to Perl_utilize() in C to make sure of that.)

Hey,

Here are few differences bewteen use and require which may make it more clear for you.

• use only expects a bareword, require can take a bareword or an expression
• use is evaluated at compile-time, require at run-time
• use implicitly calls the import method of the module being loaded, require does not
• use excepts arguments in addition to the bareword (to be passed to import), require does not
• use does not behave like a function (i.e can't be called with parens, can't be used in an expression, etc), whereas require does

Sushil Kumar

the values would get lost on each time the required file got hit.

In What's the difference between require and use?

    1)  do $file is like eval `cat $file`, except the former
    1.1: searches @INC and updates %INC.
    1.2: bequeaths an *unrelated* lexical scope on the eval'ed code.
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It is the unrelated bit; in the eval'ed code lexicals from the including code are not visible. Consider:

# file foo.pl
print $var,"\n";
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# requiring code
$var = 'foo';
require 'foo.pl';
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# requiring code
my $var = 'foo';
require 'foo.pl';
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our $var;
for $var ( qw(foo bar quux) ) {
    require 'foo.pl';
}
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See also use, require, do or what?

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                              /\_¯/(q    /
----------------------------  \__(m.====·.(_("always off the crowd"))."·
");sub _{s./.($e="'Itrs `mnsgdq Gdbj O`qkdq")=~y/"-y/#-z/;$e.e && print}

1) Exporter is a way to export names into your namespace. If you use a module that doesn't use Exporter or something similar, you can still use the module, but for example a sub DoPiff() in module Bang cannot be called as DoPiff() (would generate an error) but only as Bang::DoPiff()

2) not really understanding the question.

3) If you don't use, require, do or eval a module, that module doesn't exist for your script.