To expand a bit on what chromatic said:

The key words in "method invocation using the METHOD CLASS_OR_INSTANCE LIST form is exactly equivalent to CLASS_OR_INSTANCE->METHOD (LIST) form." are "method invocation".

In other words, if new Foo is resolved by the perl parser as a method call it is exactly equivalent. The problem is that it isn't always. For instance, this works: 

#!/usr/bin/perl
use warnings;
use strict;

my $a = new Foo;

$a->hello;

package Foo;
sub new {
    return bless {},shift;
}

sub hello {
    print "hello";
}

[download]
output: 
hello

[download]
While this doesn't: 
#!/usr/bin/perl
use warnings;
use strict;

sub new {
    print "haha";
    return;
}

my $a = new Foo;

$a->hello;

package Foo;
sub new {
    return bless {},shift;
}

sub hello {
    print "hello";
}

[download]
output: 
Bareword "Foo" not allowed while "strict subs" in use at test.pl line 
+10.
Execution of test.pl aborted due to compilation errors.

[download]
"What should it profit a man, if he should win a flame war, yet lose his cool?"

In reply to Re^4: Is it ok to mix functional and oo programming in one package? by Joost
in thread Is it ok to mix functional and oo programming in one package? by leocharre

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