List Partition Boundary Cursor Map Tool

Description

Classify cursor before boundary as left with its original coordinate; otherwise classify right and subtract boundary for localCursor.

A list window uses a start and exclusive end or a center and radius. Boundary clamping, padding, and half-integer centers are separate conventions.

Classify cursor before boundary as left with its original coordinate; otherwise classify right and subtract boundary for localCursor.

Use List Partition Boundary Cursor Map when you need an explicit window position or edge-padding budget.

Enter length, boundary, cursor. Use the units and conventions below.
Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
Read partition, localCursor. Use the output convention below.

Classify cursor before boundary as left with its original coordinate; otherwise classify right and subtract boundary for localCursor.^[1]

Input field	Meaning and units	Accepted input
length	Length, count, or code length under the stated domain and unit convention.	Required. Safe integer; minimum 0.
boundary	Boundary	Required. Safe integer; minimum 0.
cursor	Cursor	Required. Safe integer; minimum 0.

Output field	Interpretation	Returned shape
partition	Partition	Required. Text; maximum UTF-16 length 8192.
localCursor	Local Cursor	Required. Safe integer.

json

{
  "input": {
    "length": 8,
    "boundary": 3,
    "cursor": 5
  },
  "output": {
    "partition": "right",
    "localCursor": 2
  }
}

The boundary cursor belongs to the right partition, including an empty right partition at the terminal boundary.
Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Numeric signed-zero results are exported as zero.

Inspect actual list bounds and choose whether to shift, truncate, or pad windows before extracting data.

List Run Split At Cursor
Return cursor as left and runLength minus cursor as right.
List Page Boundary Cursor Shift
Add pageSize times signed shiftPages to cursor.