Difflib

A set of helpers for computing deltas between objects.

Difflib is a partial port of python 3's difflib.

The port is meant to closely resemble the code, docs, and tests from the python implementation for easy reference between the two.

Status of the classes and functions to be ported from python

Completed:

• Class SequenceMatcher: A flexible class for comparing pairs of sequences of any type.
  • implemented as the module Difflib.SequenceMatcher
• Function get_close_matches(word, possibilities, n=3, cutoff=0.6): Use SequenceMatcher to return list of the best "good enough" matches.
  • implemented in the Difflib.SequenceMatcher module

Not Started:

• Function context_diff(a, b): For two lists of strings, return a delta in context diff format.
• Function ndiff(a, b): Return a delta: the difference between a and b (lists of strings).
• Function restore(delta, which): Return one of the two sequences that generated an ndiff delta.
• Function unified_diff(a, b): For two lists of strings, return a delta in unified diff format.
• Class Differ: For producing human-readable deltas from sequences of lines of text.
• Class HtmlDiff: For producing HTML side by side comparison with change highlights.

Installation

The package can be installed by adding difflib to your list of dependencies in mix.exs:

def deps do
  [
    {:difflib, "~> 0.1.0"}
  ]
end

Basic Usage

iex> SequenceMatcher.get_close_matches("appel", ["ape", "apple", "peach", "puppy"])
["apple", "ape"]

iex> a = "qabxcd"
iex> b = "abycdf"
iex> SequenceMatcher.get_opcodes(a, b)
[
  {:delete, 0, 1, 0, 0},
  {:equal, 1, 3, 0, 2},
  {:replace, 3, 4, 2, 3},
  {:equal, 4, 6, 3, 5},
  {:insert, 6, 6, 5, 6}
]

iex> a = "abcd"
iex> b = "bcde"
iex> SequenceMatcher.ratio(a, b)
0.75

Documentation

Complete documentation can be found at https://hexdocs.pm/difflib

Source

Code can be found at https://github.com/gschro/difflib