# Text Processing Services

The modules described in this chapter provide a wide range of string manipulation operations and other text processing services.

The `codecs` module described under Υπηρεσίες Δυαδικών Δεδομένων is also highly relevant to text processing. In addition, see the documentation for Python’s built-in string type in Τύπος Ακολουθίας (Sequence) Κειμένου — str.

- `string` — Common string operations
  - String constants
  - Custom string formatting
  - Format string syntax
    - Format specification mini-language
    - Format examples
  - Template strings ($-strings)
  - Helper functions
- `string.templatelib` — Support for template string literals
  - Template strings
  - Types
  - Helper functions
- `re` — Regular expression operations
  - Regular expression syntax
  - Module contents
    - Flags
    - Functions
    - Exceptions
  - Regular expression objects
  - Match objects
  - Regular expression examples
    - Checking for a pair
    - Simulating scanf()
    - search() vs. prefixmatch()
    - prefixmatch() vs. match()
    - Making a phonebook
    - Text munging
    - Finding all adverbs
    - Finding all adverbs and their positions
    - Raw string notation
    - Writing a tokenizer
- `difflib` — Helpers for computing deltas
  - SequenceMatcher objects
  - SequenceMatcher examples
  - Differ objects
  - Differ example
  - A command-line interface to difflib
  - ndiff example
- `textwrap` — Περιτύλιγμα και γέμισμα κειμένου
- `unicodedata` — Unicode Database
- `stringprep` — Internet String Preparation
- `readline` — GNU readline interface
  - Init file
  - Line buffer
  - History file
  - History list
  - Startup hooks
  - Completion
  - Example
- `rlcompleter` — Completion function for GNU readline