{ "category": "Information functions", "display_name": "ISFORMULA", "entry_kind": "built_in_function", "eval_api": { "method": "POST", "url": "https://handbook.dnacalc.com/api/eval" }, "function_id": "FUNC.ISFORMULA", "implementation_state": { "answer_bank": null, "detail": "Recorded: 16 workbook cells.", "dnacalc_commit": "9e1884369a678158dd82d3d74188daf986995e87", "in_catalogue": true, "state": "matches", "state_label": "Matches every recorded Excel answer", "summary": "Matches all 16 recorded answers", "workbook_corpus": { "cells": 17, "matched": 16, "pending": 1 } }, "implementations": [ { "commit": "9e1884369a678158dd82d3d74188daf986995e87", "flavour": "excel-compatibility-candidate", "language": "Rust", "name": "CalcFunc", "own_code": [ "https://github.com/DnaCalc/DnaCalc/blob/9e1884369a678158dd82d3d74188daf986995e87/crates/calc-func/src/catalogue/information.rs#L103-L103", "https://github.com/DnaCalc/DnaCalc/blob/9e1884369a678158dd82d3d74188daf986995e87/crates/calc-func/src/catalogue/information.rs#L256-L281" ], "repository": "https://github.com/DnaCalc/DnaCalc", "shared_code": [ "catalogue/aggregate::reader", "catalogue/aggregate::read_reference", "catalogue/information::unary", "catalogue/information::scalar", "catalogue/information::known", "catalogue/information::each", "catalogue/information::n", "catalogue/information::n_of", "catalogue/information::referenced" ], "source": "https://github.com/DnaCalc/DnaCalc/blob/9e1884369a678158dd82d3d74188daf986995e87/crates/calc-func/src/catalogue/information.rs#L103-L103", "state": "matches", "suite": null, "summary": "Matches all 16 recorded answers" } ], "json_url": "https://handbook.dnacalc.com/api/functions/FUNC.ISFORMULA.json", "name": "ISFORMULA", "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- **`FORMULATEXT(reference)`** returns the formula's text where `ISFORMULA` returns a boolean.\n They arrived together in Excel 2013 and are usually used together:\n `IF(ISFORMULA(A1), FORMULATEXT(A1), A1)` renders a sheet's formulas alongside its constants.\n `FORMULATEXT` returns `#N/A` where `ISFORMULA` returns `FALSE`, which is why the guard is\n worth writing.\n- **`TYPE`** explicitly cannot answer this question; Microsoft says so on its own page.\n- **`CELL(\"contents\", ref)`** returns the value, \"not a formula\" in Microsoft's own words — the\n same limitation stated a third time.\n- **`ISREF`** tests whether an expression *is* a reference; `ISFORMULA` tests what is stored at\n one. Both are reference-aware and they are easy to confuse.\n- **`ISBLANK`** is the companion in the `=\"\"` diagnosis described above.\n- **`SHEET`, `SHEETS`, `CELL`, `INFO`** are the other host-backed members of the Information\n category.\n\n\n", "how-to-implement": "\n### Notes for implementers\n\n\n1. **`ISFORMULA` cannot be answered from values.** It requires a workbook that stores cell\n *content* distinctly from cell *value*. An engine whose model is \"cells hold values\" cannot\n implement it, and should refuse rather than guess.\n2. **The reference must survive preparation unresolved.** Dereferencing loses the subject\n entirely: the value at the cell says nothing about whether a formula produced it.\n3. **The documented `#VALUE!` is a real, reachable path**, not a fallback. It fires for a\n defined name that is not a reference, which is a case an implementation must distinguish from\n an unresolvable name (`#NAME?`).\n4. **Decide the multi-cell and spill cases deliberately** and record them as decisions awaiting\n evidence; the documentation covers neither.\n\n\n", "quirks": "\n### Result and edge cases\n\n\nReturns a `Logical`.\n\n- **A cell containing a constant is `FALSE`** — including a constant that was typed as the\n result of a formula and then pasted as values, which is the workflow this function exists to\n audit.\n- **An empty cell is `FALSE`.** It contains no formula.\n- **A cell whose formula evaluates to an error is still `TRUE`.** The formula is there; its\n result is irrelevant. This is the property that makes `ISFORMULA` useful for auditing a broken\n sheet — `ISERROR` finds the symptom, `ISFORMULA` finds whether there is anything to fix.\n- **A cell whose formula returns the empty string is `TRUE`**, while `ISBLANK` on it is `FALSE`\n and it *looks* empty. The three-way disagreement between what the eye sees, what `ISBLANK`\n says and what `ISFORMULA` says is the standard way to find `=\"\"` helper columns.\n- **A spilled cell.** The anchor of a dynamic array holds the formula; the spilled-into cells do\n not hold formulas of their own. What `ISFORMULA` reports for a spilled-into cell is **not\n established here**, and it is the single most interesting open question about this function on\n a modern build.\n- **Volatility.** The function is declared `NonVolatile`, unlike `CELL` and `INFO` — editing a\n cell's *content* is a change Excel's dependency graph tracks, so `ISFORMULA` does not need to\n recalculate on a timer the way a formatting query does.\n\n\n\n### Errors\n\n\n- **`#VALUE!`** — documented, verbatim: \"If reference is not a valid data type, such as a\n defined name that is not a reference, ISFORMULA returns the #VALUE! error value.\" This covers\n a literal, a computed value, and a defined name that resolves to a constant or an expression.\n- **`#NAME?`** would arise before `ISFORMULA` runs, from an unresolvable name, in reference\n resolution ([coercion and lifting](../model/02-coercion-and-lifting.md)).\n- **`#REF!`** likewise, from a reference whose target has been deleted.\n- **Arity** — zero arguments or two. Expected to be refused at formula entry rather than\n evaluated ([the call pipeline](../model/03-call-pipeline.md)).\n\nNote that `ISFORMULA` is one of the few IS-named functions with a *documented* error return.\nThe classifiers have none; `ISFORMULA` has one because its argument can genuinely be of the\nwrong kind.\n\n\n", "sources": "- Microsoft, \"ISFORMULA function\" —\n .\n Read for this page: the description, the syntax, the `reference` argument description verbatim,\n and the `#VALUE!` remark verbatim.\n- Microsoft, \"TYPE function\" —\n .\n Read for the remark that `TYPE` cannot determine whether a cell contains a formula.\n- Microsoft, \"CELL function\" —\n .\n Read for the `\"contents\"` row, \"Value of the upper-left cell in reference; not a formula.\"\n- Handbook, [the execution context](../model/04-execution-context.md) — the workbook state a\n host query reads.\n- Handbook, [coercion and lifting](../model/02-coercion-and-lifting.md) — reference resolution\n and its failure modes.\n\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`ISFORMULA(reference)` returns `TRUE` if the referenced cell contains a formula, and `FALSE` if\nit does not.\n\nMicrosoft's description, verbatim: \"Checks whether there is a reference to a cell that contains\na formula, and returns TRUE or FALSE.\"\n\nThe important word is **contains**. `ISFORMULA` asks about the cell's *content* — is there a\nformula stored there — not about the cell's value. A cell holding `=1+1` and a cell holding the\nliteral `2` display the same thing, produce the same value everywhere downstream, and are\ndistinguished by exactly one worksheet function: this one.\n\nMicrosoft's `TYPE` page states the complementary limitation from the other side: \"You cannot use\nTYPE to determine whether a cell contains a formula.\" `ISFORMULA`, added in Excel 2013, is the\nfunction that filled that hole.\n\n\n\n### Arguments\n\n\n`reference` — required, exactly one. The published signature is `ISFORMULA(reference)`.\n\nMicrosoft's argument description, verbatim: \"Reference is a reference to the cell you want to\ntest. Reference can be a cell reference, a formula, or a name that refers to a cell.\"\n\nTwo things that sentence settles, and one it does not:\n\n- **A defined name is admissible** provided it resolves to a reference. A name that refers to a\n constant or to a formula expression is not a reference and is an error — see \"Errors\".\n- **\"A formula\" in that list means an expression that *produces* a reference**, such as\n `INDIRECT(\"A1\")` or `OFFSET(A1,0,0)`. `ISFORMULA(INDIRECT(\"A1\"))` asks whether `A1` holds a\n formula, not whether `INDIRECT(...)` is one.\n- **What it does not settle** is the multi-cell case. `ISFORMULA(A1:A10)` is not addressed by the\n documentation, and whether it spills a column of booleans on a modern build or intersects to a\n single answer is not established here.\n\nThe argument is a **reference position, not a value position**. Handing `ISFORMULA` a computed\nvalue is a failure, not a coercion, and that is exactly what the documented `#VALUE!` condition\ncovers.\n\n\n" }, "signature": { "display": "ISFORMULA(reference)", "parameters": [ { "description": null, "name": "reference", "optional": false, "repeats": false } ], "trailing_repeats": false }, "sources": { "metadata": { "admission": { "label": "implemented", "reason": null }, "arity": { "max": 1, "min": 1 }, "category": "Information functions", "classification": { "arg_preparation_profile": "RefsVisibleInAdapter", "coercion_lift_profile": "Custom", "determinism_class": "Deterministic", "error_collapse_profile": "None", "fec_dependency_profile": "Composite", "host_interaction_class": "WorkbookState", "kernel_signature_class": "Custom", "rich_value_usage": "RichBlind", "surface_fec_dependency_profile": "Composite", "thread_safety_class": "HostSerialized", "volatility_class": "NonVolatile" }, "descriptions": { "long": null, "short": "TRUE when the cell holds a formula", "short_source": "dna-calc-own" }, "docs": { "english_description": "Returns TRUE if there is a reference to a cell that contains a formula", "microsoft_url": "https://support.microsoft.com/en-us/office/isformula-function-e4d1355f-7121-4ef2-801e-3839bfd6b1e5" }, "entry_kind": "built_in_function", "localized_family_names": null, "localized_names": [ { "locale": "ar-SA", "name": "ISFORMULA" }, { "locale": "bg-BG", "name": "ISFORMULA" }, { "locale": "cs-CZ", "name": "ISFORMULA" }, { "locale": "da-DK", "name": "ER.FORMEL" }, { "locale": "de-DE", "name": "ISFORMULA" }, { "locale": "el-GR", "name": "ISFORMULA" }, { "locale": "en-AU", "name": "ISFORMULA" }, { "locale": "en-GB", "name": "ISFORMULA" }, { "locale": "en-US", "name": "ISFORMULA" }, { "locale": "es-ES", "name": "ESFORMULA" }, { "locale": "et-EE", "name": "ISFORMULA" }, { "locale": "fi-FI", "name": "ONKAAVA" }, { "locale": "fr-FR", "name": "ESTFORMULE*" }, { "locale": "he-IL", "name": "ISFORMULA" }, { "locale": "hr-HR", "name": "ISFORMULA" }, { "locale": "hu-HU", "name": "KÉPLET" }, { "locale": "id-ID", "name": "ISFORMULA" }, { "locale": "it-IT", "name": "ISFORMULA" }, { "locale": "ja-JP", "name": "ISFORMULA" }, { "locale": "ko-KR", "name": "ISFORMULA" }, { "locale": "lt-LT", "name": "ISFORMULA" }, { "locale": "lv-LV", "name": "ISFORMULA" }, { "locale": "nb-NO", "name": "ISFORMULA" }, { "locale": "nl-NL", "name": "ISFORMULE" }, { "locale": "pl-PL", "name": "CZY.FORMUŁA" }, { "locale": "pt-BR", "name": "ISFORMULA" }, { "locale": "pt-PT", "name": "É.FORMULA" }, { "locale": "ro-RO", "name": "ISFORMULA" }, { "locale": "ru-RU", "name": "ЕФОРМУЛА" }, { "locale": "sk-SK", "name": "ISFORMULA" }, { "locale": "sl-SI", "name": "ISFORMULA" }, { "locale": "sr-Latn-RS", "name": "ISFORMULA" }, { "locale": "sv-SE", "name": "ÄRFORMEL" }, { "locale": "th-TH", "name": "ISFORMULA" }, { "locale": "tr-TR", "name": "EFORMÜLSE" }, { "locale": "uk-UA", "name": "ISFORMULA" }, { "locale": "vi-VN", "name": "ISFORMULA" }, { "locale": "zh-CN", "name": "ISFORMULA" }, { "locale": "zh-HK", "name": "ISFORMULA" }, { "locale": "zh-TW", "name": "ISFORMULA" } ], "signature": { "display": "ISFORMULA(reference)", "parameters": [ { "description": null, "name": "reference", "optional": false, "repeats": false } ], "trailing_repeats": false }, "surface_name": "ISFORMULA", "version_marker": null, "xlcall": { "code": "589", "symbol": "xlfIsformula" } }, "microsoft": "https://support.microsoft.com/en-us/office/isformula-function-e4d1355f-7121-4ef2-801e-3839bfd6b1e5" }, "try_it": { "formula": "=ISFORMULA(B2)", "inputs": { "B2": 1 } }, "url": "https://handbook.dnacalc.com/functions/ISFORMULA.html", "variants": [], "versions": [] }