Types of expressions
PSLang supports the following types of expressions:
Operation | Description |
|---|---|
< string literal > | string literal |
< integer literal > | integer literal |
- < integer literal > | negate an integer |
< floating-point literal > | floating-point literal |
- < floating-point literal > | negate a floating-point literal |
$var | the value of the variable |
$var[expr] | string and array indexing |
(expr) | for clarity or to change order of evaluation |
expr + expr | addition or string concatenation |
expr - expr | subtraction |
expr * expr | multiplication |
expr ∕ expr | division |
expr % expr | modulus |
expr isin expr | is left a substring of right? |
expr == expr | equality |
expr ! = expr | inequality |
expr ≤ expr | left is less than or equal to right? |
expr < expr | left is less than right? |
expr ≥ expr | left is greater than or equal to right? |
expr > expr | left is greater than right? |
~expr | bitwise negation |
expr & expr | bitwise and |
expr — expr | bitwise or |
expr && expr | logical and |
expr—— expr | logical or |
$var++ | post increment operator |
$var– | post decrement operator |
! expr | logical negation |
func(...) | function call |
iif( test , true _ part , false _ part) | ternary operator |
A boolean expression yields an integer result, where zero is interpreted as false , and any value other than zero is interpreted as true .
Bitwise operators (~, &, —) must not be confused with logical operators ( ! , &&, ——). Although PSLang does not support “^”, the bitwise exclusive or operator (xor), you can achieve the same results using: (A & ~B ) | ( ~A & B ).
The PSLang + operator can be used with numerical values, or to append string values. In an expression such as x+y, where x is a string and y is a number, y is converted to a string and appended to x.
The ternary operator works the same way as the C++ ternary operator ( ?: ). The test expression is evaluated, and if the result is non-zero, the true _ part expression is evaluated and returned. Otherwise, the false _ part expression is evaluated and returned.