Programing with iterators and generators

• Filehandles are Iterators
• Iterators are Objects
• Common Examples of Iterators: readdir, each, and DBI

• File tree scanning
• Permutations
• Genomic Sequence Generator
• Filehandle Iterators
• A Flat-File Database
• Searching Databases Backwards
• Random Number Generation

• Alternatives to Iterators
• Filters and Transforms: map and grep for iterators
• Recursively-Constructed Iterators
• The Semipredicate Problem
• Alternative Interfaces to Iterators: Tied scalars and handles
• An Extended Example: Web Spiders