1.0.0 • Public • Published


This is a library for comparing tables, producing a summary of their differences, and using such a summary as a patch file. It is optimized for comparing tables that share a common origin, in other words multiple versions of the "same" table. It is written in Haxe, translated to Javascript for in-browser use. The library is also available as Haxe-generated PHP or C++.

For a live demo, see:

Get the core library here:

Or with node:

npm install coopyhx

The diff format used by coopyhx is specified here:

This library is a stripped down version of the coopy toolbox (see To compare tables from different origins, or with automatically generated IDs, or other complications, check out the coopy toolbox.

The program

There is a commandline utility wrapping the core functions of the library:

$ coopyhx
The coopyhx utility can produce and apply tabular diffs.
Call coopyhx as:
  coopyhx diff [--output OUTPUT.csv] a.csv b.csv
  coopyhx diff [--output OUTPUT.csv] parent.csv a.csv b.csv
  coopyhx diff [--output OUTPUT.jsonbook] a.jsonbook b.jsonbook
  coopyhx patch [--output OUTPUT.csv] source.csv patch.csv
  coopyhx trim [--output OUTPUT.csv] source.csv
  coopyhx render [--output OUTPUT.html] diff.csv

If you need more control, here is the full list of flags:
  coopyhx diff [--output OUTPUT.csv] [--context NUM] [--all] [--act ACT] a.csv b.csv
     --context NUM: show NUM rows of context
     --all:         do not prune unchanged rows
     --act ACT:     show only a certain kind of change (update, insert, delete)

  coopyhx render [--output OUTPUT.html] [--css CSS.css] [--fragment] [--plain] diff.csv
     --css CSS.css: generate a suitable css file to go with the html
     --fragment:    generate just a html fragment rather than a page
     --plain:       do not use fancy utf8 characters to make arrows prettier

The library

For Javascript use - first, include coopyhx.js on a webpage:

<script src="coopyhx.js"></script>

Or with nodejs:

var coopy = require('coopyhx');

For concreteness, assume we have two versions of a table, data1 and data2:

var data1 = [
var data2 = [

To make those tables accessible to the library, we wrap them in coopy.CoopyTableView:

var table1 = new coopy.CoopyTableView(data1);
var table2 = new coopy.CoopyTableView(data2);

We can now compute the alignment between the rows and columns in the two tables:

var alignment = coopy.compareTables(table1,table2).align();

To produce a diff from the alignment, we first need a table for the output:

var data_diff = [];
var table_diff = new coopy.CoopyTableView(data_diff);

Using default options for the diff:

var flags = new coopy.CompareFlags();
var highlighter = new coopy.TableDiff(alignment,flags);

The diff is now in data_diff in highlighter format, see specification here:

[ [ '!', '', '+++', '' ],
  [ '@@', 'Country', 'Code', 'Capital' ],
  [ '+', 'Ireland', 'ie', 'Dublin' ],
  [ '+', 'France', 'fr', 'Paris' ],
  [ '->', 'Spain', 'es', 'Barcelona->Madrid' ],
  [ '+++', 'Germany', 'de', 'Berlin' ] ]

For visualization, you may want to convert this to a HTML table with appropriate classes on cells so you can color-code inserts, deletes, updates, etc. You can do this with:

var diff2html = new coopy.DiffRender();
var table_diff_html = diff2html.html();

For 3-way differences (that is, comparing two tables given knowledge of a common ancestor) use coopy.compareTables3 (give ancestor table as the first argument).

Here is how to apply that difference as a patch:

var patcher = new coopy.HighlightPatch(table1,table_diff);
// table1 should now equal table2

Other languages

The coopyhx library is written in Haxe, which can be translated reasonably well into at least the following languages:

  • Javascript
  • PHP
  • Java
  • C#
  • C++

The Javascript translation is available via npm. PHP and C++ translations are posted on the Releases page. To make another translation, follow the Haxe getting started tutorial for the language you care about, then do one of:

make js
make php
make java
make cs
make cpp

@Floppy has made a partial native Ruby port.

Reading material


Coopyhx is distributed under the MIT License.




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