Extract a portion of a list with support for negative indices

Summary

The sublist macro extracts elements from a list between start and end positions. It supports negative indices to count from the end of the list.

Syntax 

${sublist;<start>;<end>;<list>[;<list>...]}

Parameters

  • start - Starting index (0-based, negative counts from end)
  • end - Ending index (exclusive, negative counts from end)
  • list - One or more lists to combine and extract from

Behavior

  • Combines all provided lists
  • Extracts elements from start (inclusive) to end (exclusive)
  • Negative indices count from the end
  • If start > end, they are automatically swapped
  • Returns comma-separated sublist

Examples

Get first 3 elements:

${sublist;0;3;apple,banana,cherry,date,elderberry}
# Returns: "apple,banana,cherry"

Get last 2 elements:

${sublist;-2;-0;apple,banana,cherry}
# Returns: "banana,cherry"

Skip first element:

${sublist;1;-0;red,green,blue}
# Returns: "green,blue"

Get middle elements:

${sublist;2;5;a,b,c,d,e,f,g}
# Returns: "c,d,e"

Extract from multiple lists:

${sublist;0;3;one,two;three,four,five}
# Returns: "one,two,three"

Use Cases

  • Extracting ranges from lists
  • Pagination of results
  • Removing headers or trailers
  • List slicing operations
  • Selecting specific segments
  • Windowing over lists

Notes

  • Indices are 0-based (first element is 0)
  • Negative indices count backwards (-1 adjusts to list end)
  • End index is exclusive (not included in result)
  • Start and end are swapped if start > end
  • Combines multiple list arguments first
  • See also: ${first}, ${last}, ${get} for single elements

See test cases in MacroTestsForDocsExamples.java