User:8680/tmp/AnimationWMLProgressiveStringSquareBracketExpansionSyntax

Each set of square brackets (‘[’ and ‘]’) contains a comma-separated list — an expansion list — of which each element can be:

1. a plain string — e.g., “abc” or “123”;
2. a range, expressed as two radix-10 integers, separated by a tilde — e.g., “1~5”; or
3. a repetition, notated as a string and a radix-10 integer, separated by an asterisk — e.g., “a*3”.

Ranges can not only be from a lesser number to a greater number (e.g., “1~5”), but can also be backward — from a greater number to a lesser number (e.g., “5~1”).

A single progressive string value may contain multiple expansion lists, which must all be of the same length in elements.

When a progressive string that contains expansion lists is processed to expand its expansion lists, it is transformed into a comma-separated list, which is generated as follows: