Formula syntax

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aliases:

• Formula Language Syntax tags:
• documentation
• formulas lang: en

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Language: English · Русский

Values

Type	Syntax	Examples
Number (double)	integer or decimal notation with a point	0, -3, 12.5
String (string)	single quotes	'Wall 01', ''
Boolean (bool)	true or false	true
Empty value	null	null
Number π	pi	2 * pi

String escaping

\', \\, \n, \r, \t, \f, and \b are supported. An unknown escape sequence is preserved unchanged.

'it\'s'       // it's
'a\\b'        // a\b
'line1\nline2'

Operators

Operators are listed from highest to lowest precedence.

Precedence	Operators	Purpose
1	^	Exponentiation
2	*, /, %	Multiplication, division, remainder
3	+, -	Addition/concatenation, subtraction
4	!	Logical NOT
5	>, >=, <, <=	Numeric comparison
6	==, !=	Equality and inequality
7	&	Logical AND
8	|	Logical OR

2 + 3 * 4              // 14
(2 + 3) * 4            // 20
true | false & false   // true
!(1 > 2)               // true

+ adds numbers and concatenates strings. If at least one operand is a string, the other is converted to a string. When adding a string to null, the empty value becomes an empty string; null + null returns null.

Numbers in == and != are compared with a tolerance of about 1e-9. The & and | operators evaluate both operands.

Note

Division follows double behavior: for example, 1 / 0 returns positive infinity.

Formula usage: user diagnostics, collision diagnostics, project parameter diagnostics. See also: Functions, Revit objects.