[SYMBOL] [A] [B] [C] [D] [E] [F] [G] [H] [I] [K] [L] [M] [N] [O] [P] [Q] [R] [S] [T] [U] [V] [W] [X] importing -nosticky option custom routines Exporter module and 2nd File::Basename module and subroutines 2nd use operation and @INC array require operator and use operation and indices, sorting with 2nd indirect object notation indirection applying sorting indices inheritance @ISA variable and code reusability through composition versus constructors and 2nd DESTROY method and 2nd isa method testing method invocation and 2nd multiple inheritance installation (of modules) alternate library locations alternate locations distribution considerations instance methods APIs and class methods and invoking 2nd Math::BigInt module OO modules and parameters and restricting to instance variables defined filehandles as hash keys object destruction and in subclasses 2nd instances accessors and blessed references and 2nd building defined 2nd hashes and isa method testing methods working with interfaces distribution considerations File::Basename module 2nd File::Spec module maintenance considerations version numbers and IO::File class 2nd is function (Test::More) 2nd @ISA variable features 2nd inheritance hierarchies and multiple inheritance isa method (UNIVERSAL) 2nd isa_ok function (Test::More) isnt function (Test::More) iteration versus recursion |