Indexed Interleave Tool
Interleave explicit lists with source-side and source-index provenance; retain unequal-length tails.
Description
Interleave explicit lists with source-side and source-index provenance; retain unequal-length tails.
Interleaving alternates corresponding entries from two lists. A source map makes the output reversible even when the lists have unequal lengths.
When to use this tool
Interleave explicit lists with source-side and source-index provenance; retain unequal-length tails.
- Prepare the supplied left, right fields for this operation.
- Compare the complete example with the representation used by your own input before carrying the result into another step.
How to use the tool and how it works
- Enter left, right. Use the exact text syntax, units and index conventions explained below.
- Run the tool. If input validation fails, correct the supplied fields before interpreting any result.
- Read result.values, result.sources. Interpret false, null and empty lists using the distinctions below; they can be valid outputs.
At each index, append the left entry if present and then the right entry if present. Return combined values and aligned {side,index} records; continue with the remaining side when the other ends.1
| Input field | Meaning and representation | Accepted input |
|---|---|---|
| left | left. | At most 128 strings, each at most 128 UTF-16 code units |
| right | right. | At most 128 strings, each at most 128 UTF-16 code units |
| Output field | Interpretation |
|---|---|
| result | Object containing the named outputs below. |
| result.values | The values list in the ordering and representation described above. |
| result.sources | The sources list in the ordering and representation described above. |
{
"input": {
"left": [
"a",
"b"
],
"right": [
"x"
]
},
"output": {
"result": {
"values": [
"a",
"x",
"b"
],
"sources": [
{
"side": "left",
"index": 0
},
{
"side": "right",
"index": 0
},
{
"side": "left",
"index": 1
}
]
}
}
}Limitations and assumptions
- Inputs are not required to have equal length. The tool does not sort, deduplicate or insert placeholders for a missing side.
- Every declared top-level field is required and unexpected fields are rejected. Numeric inputs must be finite; ordinary text fields are bounded to 8,192 UTF-16 code units, with tighter operation-specific limits where stated.
- Ordinary string lists have at most 128 entries of at most 128 code units each; numeric lists and matrices have separate bounded size checks. Nonfinite results and excessively large serialized outputs are rejected.
- Indexes are zero-based and spans have an exclusive end unless explicitly stated otherwise. A valid false, null or empty-list result is distinct from malformed input.
Alternative or Complementary methods
Use explicit source-index maps when rearranging data or planning missing-value fills. Keep row-major coordinates, cyclic indexes and one-based occurrence numbers distinct, and inspect null donor positions before copying values.
References
Similar or alternative tools
- Adjacent Change Indexes
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