Description
Audit uncovered portions of a finite UTC window after unioning all supplied coverage regardless of offsets; not a claim of timezone rule completeness.
An offset maps a supplied UTC coordinate to local civil coordinates by local = UTC + offset. Half-open spans include their start and exclude their end. A forward offset jump can leave local coordinates uncovered; a backward jump can give several UTC interpretations of one local value. These tools use explicit synthetic civil-second observations rather than a named-zone database.
Audit uncovered portions of a finite UTC window after unioning all supplied coverage regardless of offsets; not a claim of timezone rule completeness.
When to use this tool
Use this tool to audit uncovered portions of a finite UTC window after unioning all supplied coverage regardless of offsets; not a claim of timezone rule completeness.
How to use the tool and how it works
- Enter spansJson, start, end using the definitions below. Serialize JSON text fields in the decoded shape shown below.
- Run the operation. Resolve input-format errors before interpreting an output.
- Read result.gaps, using the stated boundary, ordering, sign and absence conventions.
Sort a copy of spans by start, intersect with the half-open requested window, and advance a covered frontier through their union. Return every uncovered [start,end] interval.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| spansJson | JSON array of {start,end,offset}: half-open UTC spans with local=UTC+offset, all in seconds. | Text, at most 8,192 UTF-16 code units; narrower grammar/range rules also apply. |
| start | Inclusive UTC or local window start in seconds, as explicitly stated by this operation. | Finite numeric value satisfying the stated comparisons. |
| end | Exclusive window end in seconds, on the same coordinate scale as start. | Finite numeric value satisfying the stated comparisons. |
These decoded structures show the examples inside JSON text fields. Supply their serialized JSON strings as input.
{
"spansJson": [
{
"start": 1,
"end": 2,
"offset": 0
},
{
"start": 3,
"end": 4,
"offset": 0
}
]
}| Output field | Interpretation |
|---|---|
| result | Object containing the fields below. |
| result.gaps | Uncovered half-open UTC [start,end] intervals in increasing order. |
{
"input": {
"spansJson": "[{\"start\":1,\"end\":2,\"offset\":0},{\"start\":3,\"end\":4,\"offset\":0}]",
"start": 0,
"end": 5
},
"output": {
"result": {
"gaps": [
[
0,
1
],
[
2,
3
],
[
4,
5
]
]
}
}
}Limitations and assumptions
- Offsets do not affect coverage; conflicting overlapping offsets can cover the same UTC region without being resolved by this operation.
- Span/transition coordinates are finite seconds within ±10¹² and offsets within ±86,400 seconds. Spans require start<end. No IANA database, calendar parsing, daylight-saving inference or leap seconds are included.
- Every declared outer field is required and unknown outer fields are rejected. Strings and JSON text have size limits, lists are bounded to 128 entries, and JSON nesting/node counts are bounded. Tighter operation-specific bounds stated above take precedence.
- Ordinary numeric outputs must be finite and within safe-integer magnitude. Exact large lengths/counts use decimal strings. Original record indexes and code-unit positions are zero-based; span ends are exclusive unless stated otherwise.
Alternative or Complementary methods
Keep all timestamps on one origin and in seconds, and retain gaps or competing observations. Use a maintained time-zone library when real dates, named zones or historical rules are required.
References
Similar or alternative tools
- Time Zone Offset Span Adjacent Compactor
Compact only adjacent ordered touching spans with exactly equal offsets, rejecting reversed/overlapping input rather than hiding conflicts.
- Time Zone Offset Span Overlap Conflicts
Report every positive-length UTC span overlap with unequal offset evidence; touching or identical offsets are not conflicts.