Expressions

Expressions in Jayvee are arbitrarily nested statements. They consist of:

• literals (e.g., numbers 5 or strings "Example")
• variables (e.g., declared by from properties in Transforms)
• operators (e.g., * or sqrt)

Expressions get evaluated at runtime by the interpreter to a Built-in ValueType.

Example

The following expression is evaluated to the integer 10: (2 + 3) * 2

The following expression is evaluated to the integer 3: floor (3.14)

The following expression is evaluated to the boolean true: "Example" == "Example"

List of Operators

Arithmetics (binary operators)

• + for addition, e.g., 5 + 3 evaluates to 8
• - for subtraction, e.g., 5 - 3 evaluates to 2
• * for multiplication, e.g., 5 * 3 evaluates to 15
• / for division, e.g., 6 / 3 evaluates to 2
• % for modulo, e.g., 5 % 3 evaluates to 2
• pow for power, e.g., 2 pow 3 evaluates to 8
• root for root, e.g., 27 root 3 evaluates to 3

Arithmetics (unary operators)

• + for positive signing, e.g., +5 evaluates to 5
• - for negative signing, e.g., -5 evaluates to -5
• sqrt for square root, e.g., sqrt 9 evaluates to 3
• foor for flooring a number, e.g., floor 5.3 evaluates to 5
• ceil for ceiling a number, e.g., floor 5.3 evaluates to 6
• round for rounding a number, e.g., floor 5.3 evaluates to 5

Relational (binary operators)

• < for smaller, e.g., 3 < 3 evaluates to false
• <= for smaller or equal, e.g., 3 <= 3 evaluates to true
• > for greater, e.g., 3 > 3 evaluates to false
• >= for greater or equal, e.g., 3 >= 3 evaluates to true
• == for equal, e.g., 3 == 3 evaluates to true
• != for not equal, e.g., 3 != 3 evaluates to false

Logical (binary operators)

• and for a logical and (both need to be true to evaluate to true)
• or for a logical or (at least left or right needs to be true to evaluate to true)
• xor for a logical xor (either left or right needs to be true to evaluate to true)

Logical (unary operators)

• not for logical negation, not true evaluates to false

Others (binary operators)

• matches for a regex match, e.g., "A07" matches /^[A-Z0-9]*$/ evaluates to true
• in for inclusion in an array, e.g., "a" in ["a", "b", "c"] evaluates to true

Operator Details

in Operator

The in operator checks whether a value is included in a collection of values. For example:

4.5 in [3, 6.5] // evaluates to false
3 in [3.0, 6.5] // evaluates to true
"a" in ["a", "b", "c"] // evaluates to true

The operator supports text, integer and decimal values as operands. The compatibility of left and right operand types follows these rules:

• For the in operator we have a type for the needle (left operand) and a type for the elements in the haystack (right operand).
• There is an automated type conversion as long as it is lossless and clearly defined (integer to decimal as of now).
• We allow any combination of operands that has either: (i) An automated type conversion from needle type (left operand) to the type of the elements in the haystack (right operand), or (ii) the other way around.

Further reading

For a deeper documentation of how expressions and operators work internally, refer to the developer docs.