{ "category": "Operators", "display_name": "Intersection of references (space)", "entry_kind": "built_in_operator", "eval_api": { "method": "POST", "url": "https://handbook.dnacalc.com/api/eval" }, "function_id": "FUNC.OP_INTERSECTION_REF", "implementation_state": { "answer_bank": null, "detail": "Handled by the formula layer, which owns references; answers are recorded through whole formulas, not attributed to the operator.", "dnacalc_commit": "9e1884369a678158dd82d3d74188daf986995e87", "in_catalogue": false, "state": "unmeasured", "state_label": "Implemented, no recorded answers attributed to it", "summary": "Implemented; no recorded answers are attributed to this entry", "workbook_corpus": null }, "implementations": [ { "commit": "9e1884369a678158dd82d3d74188daf986995e87", "flavour": "excel-compatibility-candidate", "language": "Rust", "name": "CalcFunc", "own_code": [ "https://github.com/DnaCalc/DnaCalc/blob/9e1884369a678158dd82d3d74188daf986995e87/crates/calc-fml/src/eval/refops.rs#L76-L98" ], "repository": "https://github.com/DnaCalc/DnaCalc", "shared_code": [ "eval/refops::reference", "eval/refops::references", "eval/refops::bounds", "eval/refops::area" ], "source": "https://github.com/DnaCalc/DnaCalc/blob/9e1884369a678158dd82d3d74188daf986995e87/crates/calc-fml/src/eval/refops.rs#L76-L98", "state": "unmeasured", "suite": null, "summary": "Implemented; no recorded answers are attributed to this entry" } ], "json_url": "https://handbook.dnacalc.com/api/functions/FUNC.OP_INTERSECTION_REF.json", "name": "OP_INTERSECTION_REF", "notes": [], "schema": "efh.function-reference/v1", "section_order": [ "what-it-does", "try-it", "quirks", "how-to-implement", "version-differences", "alternatives" ], "sections": { "alternatives": "\n### Relationships\n\n\n- [`FUNC.OP_RANGE_REF`](FUNC.OP_RANGE_REF.md) — the join; this operator is the meet.\n- [`FUNC.OP_UNION_REF`](FUNC.OP_UNION_REF.md) — the list constructor.\n- [`FUNC.OP_IMPLICIT_INTERSECTION`](FUNC.OP_IMPLICIT_INTERSECTION.md) — a *different*\n operation with a confusingly similar name. `@` scalarizes one operand relative to the\n calling cell; this operator intersects two references with each other. They are not\n variants of one idea.\n- [`FUNC.OP_TRIM_REF_LEADING`](FUNC.OP_TRIM_REF_LEADING.md) and its siblings — the\n whitespace-normalization operators, which exist because whitespace around references is\n meaningful enough to need identities of its own.\n- `INDEX`, `OFFSET`, `XLOOKUP` — the modern, explicit ways to name a cell at the crossing of\n two coordinates, and what most workbooks should use instead.\n- `IFERROR` — because `#NULL!` is an error like any other and can be trapped.\n\n\n", "how-to-implement": "\n### Notes for implementers\n\n- The empty check must come before any dereference. Producing an empty area and letting a\n consumer fail on it gives the wrong error code.\n- Whitespace handling is a parser responsibility, but the operator identity must not be lost\n in it: a formula's stored form records the spacing, which is exactly why the trim-reference\n operators exist as separate identities.\n- Sheet-qualified and multi-area operands are outside the contract's admitted slice; an\n implementation should state what it does rather than assume.\n\n\n", "quirks": "\n### Result and edge cases\n\n- **No overlap.** `#NULL!`.\n- **Partial overlap.** The overlapping rectangle, which may be a single cell, a row segment,\n a column segment, or a block.\n- **Whole-row against whole-column.** `1:1 A:A` is the single cell at their crossing — the\n mechanism behind the defined-name idiom above.\n- **Multi-area operands.** Intersecting a multi-area reference (from\n [`FUNC.OP_UNION_REF`](FUNC.OP_UNION_REF.md)) with an area is not in the contract's admitted\n slice, and the result shape is not settled here.\n- **Non-reference operands.** No intersection exists; the result is an error.\n- **Cross-sheet operands.** Not covered by the admitted slice.\n\n\n\n### Errors\n\n\n| Error | Condition |\n|---|---|\n| `#NULL!` | The operands designate no common cell. |\n| `#REF!` | An operand is not a usable reference, or is no longer valid. |\n| any incoming error | An error operand propagates. |\n\n", "sources": "- `data/presence/FUNC.OP_INTERSECTION_REF.json` — implementing module\n `earlier-implementation/operator_reference_family.rs`.\n- Handbook `content/model/01-value-universe.md` — the `#NULL!` definition (\"the intersection\n of ranges that do not intersect (the space operator)\") and the reference shapes.\n- Handbook `content/model/03-call-pipeline.md` — operators as functions; reference-visible\n argument preparation.\n\n", "version-differences": "No comparison between specific Excel builds is recorded here yet. This does not establish that all builds behave alike.", "what-it-does": "\n`A B` — two references separated by a space — returns the reference designating the cells\nbelonging to both.\n\n**When the operands do not overlap, the result is `#NULL!`.** The contract records this\ndirectly, and chapter 01's error table defines `#NULL!` as exactly that: the intersection of\nranges that do not intersect, produced by the space operator. This is the only place in the\nentire function surface where `#NULL!` originates. If a workbook shows `#NULL!`, an\nintersection somewhere came up empty — very often an accidental one, because the operator is\nspelled with a character that is otherwise invisible.\n\nThat invisibility is the operator's defining hazard. `=SUM(A1:A5 B1:B5)` looks like a typo\nfor a comma and evaluates as an intersection; `=A1 A2` is a valid expression. Whitespace\ninside a formula is not always insignificant, and this is why.\n\nThe classic *intentional* use is with defined names: if `Revenue` names a column and `Q2`\nnames a row, then `=Revenue Q2` reads the cell where they cross. That idiom is the reason the\noperator exists and is worth knowing even if you never write another one.\n\n\n\n### Arguments\n\n\n| Position | Name | Meaning |\n|---|---|---|\n| 0 | `A` | First reference. Required. |\n| 1 | `B` | Second reference. Required. |\n\nArity is exactly 2; no optional arguments, no defaults. Intersection is commutative and\nassociative on areas, so chains behave as expected. Both operands must be reference-shaped;\nthe contract records the admitted operand shapes as A1-style cells, areas, whole rows and\nwhole columns.\n\n\n" }, "signature": { "display": "A B", "parameters": [ { "description": null, "name": "A", "optional": false, "repeats": false }, { "description": null, "name": "B", "optional": false, "repeats": false } ], "trailing_repeats": false }, "sources": { "metadata": { "admission": { "label": "formula_layer", "reason": null }, "arity": { "max": 2, "min": 2 }, "category": "Operators", "classification": { "arg_preparation_profile": "RefsVisibleInAdapter", "coercion_lift_profile": "Custom", "determinism_class": "Deterministic", "error_collapse_profile": "None", "fec_dependency_profile": "RefOnly", "host_interaction_class": "WorkbookState", "kernel_signature_class": "Custom", "rich_value_usage": "RichBlind", "surface_fec_dependency_profile": "RefOnly", "thread_safety_class": "SafePure", "volatility_class": "NonVolatile" }, "descriptions": { "long": null, "short": null, "short_source": "no-short-description" }, "docs": null, "entry_kind": "built_in_operator", "localized_family_names": null, "localized_names": [], "signature": { "display": "A B", "parameters": [ { "description": null, "name": "A", "optional": false, "repeats": false }, { "description": null, "name": "B", "optional": false, "repeats": false } ], "trailing_repeats": false }, "surface_name": "OP_INTERSECTION_REF", "version_marker": null, "xlcall": null }, "microsoft": null }, "try_it": { "formula": "=SUM(B2:C3 B3:C4)", "inputs": { "B2": 1, "B3": 2, "B4": 3, "C2": 10, "C3": 20, "C4": 30 } }, "url": "https://handbook.dnacalc.com/functions/OP_INTERSECTION_REF.html", "variants": [], "versions": [] }