Expression Syntax
- Updated2026-02-04
- 2 minute(s) read
Use expression syntax similarly to the syntax used in text-based programming languages.
Your expression syntax must conform to the allowed functions and operator precedence in the Expression component of the Property Browser.
The expression syntax is summarized below using Backus-Naur Form (BNF notation). The
summary includes non-terminal symbols: identifier, number, array-size,
floating-point-type, integer-type, left-hand-side, assignment-operator, and
function.
Note Italicized symbols are terminal symbols given exactly as how
you should reproduce them. The symbol # denotes any number of the term
following it.
assignment:
- expression
- left-hand-side assignment-operator assignment
expression:
- expression binary-operator expression
- unary-operator expression
- expression unary-operator
- expression ? expression : expression
- ( expression )
- identifier
- constant
- function-name ( argument-list )
left-hand-side:
- identifier
- identifier array-subscription
array-subscription:
- [assignment]
assignment-operator: one of
- = += –= *= /= >>= <<= &= ^= |= %= **=
binary-operator: one of
- + – * / ^ != == > < >= <= >> << && || & | % **
unary-operator: one of
- – ! ++ –– ~
argument-list:
- expression
- expression , argument-list
constant:
- pi
- true
- false
- number
non-digit: one of
- _ a~z A~Z
digit: one of
- 0 1 2 3 4 5 6 7 8 9
nonzero-digit: one of
- 1 2 3 4 5 6 7 8 9
binary-digit: one of
- 0 1
hex-digit: one of
- 0 1 2 3 4 5 6 7 8 9 a b c d e f A B C D E F
identifier:
- non-digit [non-first-character]
non-first-character:
- non-digit [non-first-character]
- digit [non-first-character]
number:
- integer-constant
- float-constant
integer-constant:
- decimal-constant
- binary-constant
- hex-constant
decimal-constant:
- nonzero-digit #digit
binary-constant:
- 0b #binary-digit
- 0B #binary-digit
hex-constant:
- 0x #hex-digit
- 0X #hex-digit
float-constant:
- fraction exponent-part
- decimal-constant exponent-part
fraction:
- #digit . digit #digit
exponent-part:
- e [sign] #digit
- E [sign] #digit
sign: one of
- + -
Related Information
- Expression Functions
Use functions when editing expressions in the Property Browser.
- Expression Operator Precedence
Operators in real-time sequence expressions have an order to when they execute.