gridcraft/docs/macros.md

# Macros

> **Last updated:** 2026-10-25 · **Change:** minor (checking macros before they run: the footprint, shifting, `macro.check`)

GridCraft macros are typed, declarative lists of commands, not VBA. Every step runs a GridCraft
command (the same ids the ribbon, CLI and MCP use) or one of three bounded control steps. A macro
declares the inputs it works on, runs as one undo step, rolls all workbook changes back on an
error (a file it already wrote stays), checks where its results will land before it writes them,
and does not touch files without permission.
Agents run macros with `macro.run` like any other command.

This page describes the macro format, its tokens, and running and checking macros. `macro.run`
checks the macro, its inputs, its parameters and the policy before it runs, works out where it
writes, and checks each step as it runs; `macro.check` reports what a run would do without
running it. The engine has no macro debugger, recorder or management commands in this version,
and no macro interface.

## A macro

```json
{
  "name": "Totals",
  "description": "Adds a total next to the amounts",
  "inputs": [{"name": "Input", "header": true, "cols": [2, 2], "colTypes": ["text", "number"]}],
  "output": {"anchor": "Input.right(2).cell(1,2)", "onConflict": "ask"},
  "steps": [
    {"type": "command", "id": "cell.set", "params": {"cell": "Output", "input": "Total"}},
    {"type": "command", "id": "cell.set", "params": {"cell": "Output.offset(1,0)", "input": "=SUM({{Input.data.col(2)}})"}},
    {"type": "repeat", "over": "Input.data", "of": "rows", "max": 1000, "body": [
      {"type": "if", "cell": "Row.cell(1,2)", "op": "gt", "value": 100,
       "then": [{"type": "command", "id": "home.bold", "params": {"range": "Row"}}]}
    ]},
    {"type": "stop", "message": "Done."}
  ],
  "permissions": []
}
```

- **Steps**: `command` (`id`, `params`), `repeat` (each row or column of `over`, at most `max`
  times), `if` (`cell` compared with `value` by `eq`, `ne`, `gt`, `ge`, `lt`, `le`, `empty`,
  `notEmpty` or `contains`; `then` and `else` lists) and `stop` (`message`; `rollback: true`
  undoes the run). Every step can carry `enabled`, `breakpoint` and `note`. The short form
  `{"command": "cell.set", "params": {…}}` is accepted for a command step.
- **Inputs**: `kind` (`cell` or `range`), `rows` and `cols` as `[min, max]` (0 for no maximum;
  rows exclude the header), `header`, `colTypes` (`number`, `text`, `date`, `bool`, `any`),
  `nonEmpty` and `defaultRef`. These declare what a range must look like for the macro to work
  on it. An input's name is letters, digits and `_`, starting with a letter, and is neither a
  token of its own (`Output`, `Row`, `Column`, `Name`) nor something that reads as a cell
  reference (`Q1`), so a step written with plain A1 text keeps meaning the cell. The declaration
  is checked as a whole: neither `rows` nor `cols` may have a least above its most, a `cell` input
  has one row and one column (`[1, 1]`, or the default `[1, 0]`), no header and at most one column
  type, and no input lists more column types than it allows columns. A run binds each input
  to the range it is given, its default, or (for the first input) the selection, and refuses
  with messages that name the cells: "Input column 2 (Amount) must hold numbers; C4 holds text."
- **Limits**: 1,000 macros a workbook, 10,000 steps a macro, Repeat and If nested 4 deep, and 64
  inputs a macro. Names (of macros and inputs) and command ids are at most 255 characters;
  descriptions, step notes, Stop messages and If values (as JSON) 4,096; references and tokens
  (`output.anchor`, `defaultRef`, a Repeat's `over`, an If's `cell`) 1,024; a shortcut 64. A
  macro lists at most 256 permissions, each a command id, and an input at most 16,384 column
  types. One-line fields hold no line breaks or other control characters, and a command id is
  letters, digits, `.` and `_`. A command step's `params` are bounded only by the size of the
  whole macro (4,194,304 characters of JSON). A macro read from a file that breaks any of these is
  left out with a warning; it is never changed to fit. When a macro runs, a Repeat whose range has
  more rows or columns than its `max` is refused, and a run executes at most 100,000 steps (each
  pass through a Repeat counts), passes its commands at most 256 MB of parameters, all steps
  together, and takes at most 60 seconds, all three shared by the footprint dry runs and the run
  itself (`timeLimit` to change the time; the web build has no clock, so there only the step and
  parameter limits apply).

## Tokens

References in step parameters can be tokens, worked out when the step runs:

| Token | Means |
|---|---|
| `Input`, or another input's name | the range the input is bound to |
| `Output` | the output rule's anchor |
| `Row`, `Column` | the current row or column of the Repeat around the step |
| `Name:Total` | a defined name, or a table's data |

Methods narrow or move a range and chain: `col(2)` or `col("Amount")`, `row(1)`, `cols(2..3)`,
`rows(2..)`, `cell(r,c)` (relative to the top-left cell; `cell(0,1)` is the cell above),
`offset(r,c)`, `resize(h,w)`, `data` (without the header row), `below(n)` and `right(n)`.
`col("Amount")` looks the name up in an input's header row, directly or after `data`; on a range
without a header row it is refused. A defined name can hold periods: `Name:Sales.Q1` is the name
`Sales.Q1`, and `Name:Sales.Q1.cell(1,1)` its first cell, because the longest name or table that
exists is used and methods follow it.

Write a token as the whole value of a reference parameter (`cell`, `range`, `target`, keys ending
in `Cell` or `Range`…), as `{"$ref": "Input.col(2)"}` anywhere, or as `{{Input.col(2)}}` inside
any string, such as a formula; `{{{{` in a string is a literal `{{`. Under the general keys that
other commands use for plain words (`to`, `from`, `at`, `area`, `source`, `target`,
`destination`, `location`), a bare `Row` or `Column` stays text (a replacement word, a pivot
area); write `Row.col(2)`, `{{Row}}` or `{"$ref": "Row"}` there. Plain A1 references stay
absolute; a `Name:` anchor follows inserted rows. A reference with a sheet name is never a token,
so `Output!A1` is a cell on a sheet called Output, even when a token or input has that name.
`Input.data` on a range that is only a header row, and `Name:` of a table with no data rows, are
refused rather than read as the header.

## Running

`macro.run {name, inputs?, onConflict?, overwrite?, approve?, timeLimit?}`:

1. **Policy.** File commands other than Properties, exports and printing (such as Open, Save
   and Close), app, window (including New Window, Hide and Unhide), automate and macro commands,
   and Undo and Redo, never run in a macro. File › Properties runs, and so do exports and
   printing (`file.exportPdf`, `exportCsv`, `exportHtml`, `print`, `printPreview`, `saveBytes`)
   that only produce bytes. Reading or writing a file (`data.getData`, `data.fromTextCsv`,
   `insert.picture` or `pageLayout.background` with a `path`, or an export or print with a
   `path`) needs the command in the macro's `permissions`. Any `path` other than `null` counts,
   including a blank one and a token, and the policy is checked again on the parameters as they
   are when the step runs. A macro that touches files, or that came with a workbook opened from
   a file, runs once the person approves it: the call fails with `approve: …` and runs with
   `approve: true`. Approval lasts for the session, until the macro changes. Every step other
   than an approved file step runs inside the file sandbox that scripts use, so no other
   parameter reaches a file either.
2. **Footprint.** Unless the conflict rule is `overwrite`, the macro first runs in dry-run mode on
   the real workbook, and everything is put back. Cells it would write outside its inputs that
   hold data, and sheets and objects it would delete, are conflicts, handled by `onConflict` (or
   the macro's `output.onConflict`): `ask` (the call fails with `confirm: …`; `overwrite: true`
   answers it), `fail`, `overwrite`, `shiftDown` or `shiftRight` (Insert Cells makes room, then
   the footprint is checked again). Steps that touch files, and Solver, end the dry run early;
   the footprint then says it is partial. Unless the rule is `overwrite`, the run also checks
   every step as it goes, since the footprint can miss a write: it is partial, or a value such as
   RAND or NOW sends the run another way than the dry run. A step that writes over cells, sheets
   or objects that held data when the run started stops the run and rolls the workbook back (a
   file already written stays): it asks (`confirm: …`) under `ask` and fails otherwise, since
   shifting can't make room that late. Moving cells that hold data, as inserting or deleting rows
   or cells above them does, counts as writing over them, in the footprint and in this check, and
   so does a formula whose references such a move rewrites: both compare cells by place, so they
   may ask about data that only moved, never the other way.
3. **Run.** One undo step, "Run Macro: Totals". Any error rolls the whole run back and names the
   step: `Step 3.1 (cell.set): …` (paths are 1-based; `2.1` is inside a Repeat, `4.then.1` inside
   an If). The message ends "Nothing was changed.", or names the files the run already wrote,
   which stay. An input the macro doesn't have, an input that isn't reference text, and
   `onConflict`, `overwrite`, `approve` or `timeLimit` of the wrong kind are refused rather than
   ignored. When a step inserts, deletes or moves sheets, rows, columns or cells, the inputs, the
   output and the range of a Repeat in progress move with their cells, as references in formulas
   do; a step that deletes one of them, or changes the size of a range a Repeat is going over,
   stops the run.

`macro.check {name, inputs?, onConflict?, overwrite?, timeLimit?}` reports the bound inputs, the
output anchor, any approval needed and the footprint, and puts back everything the dry run
changed. `ok` says whether `macro.run` with the same parameters would go ahead without a question;
when it wouldn't, `errors` says why: the run would fail at a step, a Stop step rolls it back, it
would write over data under `ask` or `fail`, shifting can't make room (the check shifts and
checks again, then puts everything back), or the run would go past
the step or parameter limit counting the dry runs before it. The random numbers RAND gives move
on, as after any recalculation.

## Storage

Macros are saved in the workbook: as a field in GridCraft's JSON format, and in xlsx as hidden
defined names (`_gc_macro_<n>_<k>`, the macro's JSON split into string literals within Excel's
limits), which other spreadsheet applications keep but do not run. A visible name of that shape
is someone's own name: opening a file leaves it alone, and saving stores the macros under indices
it does not use.

Each macro carries its format version, `v` (1 in this version; a missing `v` reads as 1). When a
file is opened, a macro in a newer format (a `v` above 1) is kept unread, with a warning: this
version can't show or run it, and saving writes it back unchanged, so the newer
version gets it back whole. It is never read in part. Kept macros count toward the 1,000-macro
limit after the readable ones, and one too large for an xlsx file is left out. A macro that is
damaged or over the limits is left out with one warning, and the rest of the workbook and its
other macros open; a macro that was left out is not in the saved file.

## Automate scripts and VBA

Automate scripts (`automate.recordActions`, `newScript`, `allScripts`, `runScript`,
`deleteScript`) are an older, separate feature. They keep their commands, parameters, storage
(`_sc_scripts`) and results, and View › Macros (`view.macros`) still lists them. Macros neither
read nor change them; a workbook can hold a script and a macro with the same name.

A VBA project in an `.xlsm` or `.xltm` file is preserved on save and never run. GridCraft macros
are stored apart from it.