nicely

Python Fancy Printer

Abstract

The nicely package is yet another 'pretty printer'.

It is meant to:

• have a readable and consistent output.

  • Nested levels are indented. (the indentation string is configurable (4 spaces by default))
  • The sequences and the mapping keys are sorted. (can be disabled)
  • Mapping keys are padded. (so the values are aligned)
  • The data types may be shown. (disabled by default)

• be simple to use.

  • Only one class is required.
  • Convinience functions are also provided.

• be extensible

  • If the provided support for standard types doesn't suit your need, it's easy to modify it.
  • Any object can easaly be supported.

• be able to handle large data structure.

  • Sequences, mappings, strings and multi-lines can be truncated as needed.
  • Mapping items can be omitted based on regex.

Usage

There are several ways to use nicel.

The Printer class:

from nicely import Printer

p = Printer()
p.print(some_data_structure)

The Printer.print method sends a formatted representation of its argument to a file-like destination (stdout by default).

The dump function:

from nicely import dump

dump(some_data_structure)

The dump function uses the Printer class to 'dump' its argument on stdout as well as to a file ('nicely.dump' by default).

The format function:

from nicely import format

string = format(some_data_structure)

The format function uses the Printer class to get a string representation of an object.

Data Types support

There are 2 ways for an object to be "printable" / "dumpable":

The Formatter class

The Printer class needs one Formatter for each supported data type (exept for string).

A set of default Formatter is provided by the formatters module for Python's builtin types and should be good enough for most purposes.

These formatters can be modified or extended at will to support new types or modify the output for existing ones.

The print method

Any object can become 'printable' by implementing the print method which will call the Printer's methods in appropriate ways.

Installation

$ pip install nicely