Perl Module Basics

string or as a reference to a subroutine. The string form is preferred since it allows 

for a child class to override an overloaded method. Table 2 3 lists the overloadable 

operations.

Table 2 3. Overloadable Operations

Operation Type

Symbols

Conversion

""

 0+ bool

Arithmetic

+ +=    = * *= / /= % %= ** **= ++   

String

x x= . .=

Numeric comparison

< <= > >= == != <=>

String comparison

lt le gt ge eq ne cmp

Bitwise

<< >> <<= >>= & ^ | neg ~

Logical

!

Transcendental

atan2 cos sin exp abs log sqrt int

Iteration

<>

Dereferencing

${} @{} %{} &{} *{}

Special

nomethod fallback =

This method will be called with three parameters the object itself, the variable 

on the opposite side of the operator, and metadata about the operator call 

including the order of the arguments.

NOTE Overloading in Perl has little in common with overloading in 

other languages. For example, in C++  overloading  refers to the ability 

to have two functions with the same name and different parameter 

types. Currently Perl does not have this ability, but rumor has it Perl 6 

will change that.

Overloading Conversion

Overloading's most useful feature is not its ability to overload math operators. I'll 

be covering that in a moment, but unless you're inventing new mathematical 

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