Regroupement de liste

In this example, we group the coordinates of a regular hexagon. The input coordinates are given as a space-separated list "x1 y1 x2 y2 x3 y3 …". What we want to do is create vector point pairs such as "(x1, y1); (x2, y2); (x3, y3); …". To do that, we use the space character as the input coordinate separator, and to create vectors, we group them by pairs. We wrap the coordinates in parentheses, put a comma between the x and y group items, and a semicolon between individual groups.

This example demonstrates grouping of list items and creates 9 groups of 3 items. The input list contains all alphabet letters (26 letters, separated by a semicolon) and the output is groups of letter trigrams. As the last group is missing one letter, we enable padding and add the underscore symbol as the padding element.

In this example, we use our list item grouper to convert a food list to tab-separated values (TSV). As spaces are chaotically used between the items of the input list, we use the item separating regular expression "\s+" to match them. We create a TSV with three columns (three groups), separate them with a tab character, and put newlines between the groups.