Scripting

Lido provides formulas for running JavaScript code, creating reusable lambda functions, and mapping functions over data. These are non-action formulas — they execute immediately during formula evaluation.

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EVALJS

Evaluates a JavaScript expression and returns the result. The code runs in a sandboxed QuickJS environment with a 5-minute timeout.

Syntax:

=EVALJS(code)

Parameters:

Parameter	Description	Required
code	JavaScript code to evaluate	Yes

Allowed return types: number, string, boolean. For other types, return them as a JSON string.

Examples:

=EVALJS("2 + 2")
→ 4

=EVALJS("'hello'.toUpperCase()")
→ "HELLO"

=EVALJS("JSON.stringify({a: 1, b: [2, 3]})")
→ '{"a":1,"b":[2,3]}'

Tips

• EVALJS runs in an isolated sandbox — it cannot access the DOM, network, or spreadsheet data directly
• To pass spreadsheet data into EVALJS, concatenate it into the code string: =EVALJS("'" & A1 & "'.split(',').length")
• For complex logic, combine EVALJS with LAMBDA and MAP to process table data row by row

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LAMBDA

Creates a reusable function that can be passed to MAP or stored in a named cell for use as a custom formula.

Syntax:

=LAMBDA(arg1, arg2, ..., formula)

Parameters:

Parameter	Description	Required
arg1, arg2, ...	Parameter names for the function	Yes (at least one)
formula	The formula body that uses the parameters	Yes (last argument)

The last argument is always the formula body; all preceding arguments are parameter names.

Example:

=LAMBDA(x, y, x * y + 1)

Creates a function that takes two arguments and returns x * y + 1.

Named Cell Lambdas

LAMBDA becomes especially powerful when combined with named cells. If you name a cell (by editing the cell name input to the left of the formula bar) and that cell contains a LAMBDA formula, the cell name becomes a callable formula anywhere in your spreadsheet.

Example:

1. In cell A1, enter: =LAMBDA(x, x * 2 + 1)
2. Name the cell DOUBLE_PLUS_ONE (via the name box)
3. Now use it anywhere: =DOUBLE_PLUS_ONE(5) → 11

This pattern is especially useful with EVALJS for creating reusable JavaScript macros:

1. Name a cell PARSE_CSV
2. Enter: =LAMBDA(text, EVALJS("'" & text & "'.split(',').length"))
3. Use it: =PARSE_CSV("a,b,c") → 3

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MAP

Applies a function (LAMBDA) to each row of one or more columns/ranges and returns the results as a column.

Syntax:

=MAP(values, function)
=MAP(values1, values2, ..., function)

Parameters:

Parameter	Description	Required
values1, values2, ...	Column ranges or table column references to iterate over	Yes (at least one)
function	A LAMBDA function or reference to a named cell containing a LAMBDA	Yes (last argument)

All value columns must have the same number of rows. The function receives one value per column for each row.

Examples:

Single column:

=MAP(A1:A10, LAMBDA(x, x * 2))

Doubles each value in A1:A10.

Multiple columns:

=MAP(Orders[@Price], Orders[@Quantity], LAMBDA(price, qty, price * qty))

Multiplies Price by Quantity for each row in the Orders table.

With a named cell lambda:

=MAP(A1:A10, MY_CUSTOM_FUNCTION)

Where MY_CUSTOM_FUNCTION is a named cell containing a LAMBDA formula.

Tips

• MAP works with cell ranges (A1:A10), table column references (Orders[@Price]), or evaluated arrays
• When using multiple value arguments, they must all have the same number of rows
• The function argument must be a LAMBDA (inline or referenced by name)