Operators
The Freedom Scientific Scripting language supports the use of many operators. Operators are grouped by usage at heading level 2 elements, and each operator within that group is at a heading level 3 element along with its relevant descriptive information. Where the name of the operator is a punctuation character symbol or group of characters, it is spelled out in parentheses after the character or group of characters.
Unless otherwise specified, the version where the operator was first made available to the Scripting language was JAWS 4.5.
Arithmetic Operators
Operator: + (plus) Use the + (plus) operator in equations to indicate addition or to concatenate strings enclosed in quotation marks.
Operator: - (minus) Use the - (dash) minus operator in equations to indicate subtraction.
Operator: * (asterisk) Use the * (asterisk) operator in equations to indicate multiplication.
Operator: / (slash) The / slash operator is used in equations to indicate division.
Operator: % (percent) The result of the modulus operator (%) is the remainder when the first operand is divided by the second.
Comparison Operators
Operator: == (double equal) The == (double equal) operator asks whether the first condition is equal to the second condition.
Operator: != (is not equal to) The != (exclamation mark equal to) operator asks whether the first condition is not equal to the second condition.
Operator: >= (greater than or equal to) The >= (greater than or equal to) operator asks whether the first condition is greater than or equal to the second condition.
Operator: > (greater) The > (greater than) operator asks whether the first condition is greater than the second condition.
Operator: <= (less than or equal to) The <= (less than or equal to) operator asks whether the first condition is less than or equal to the second condition.
Operator: < (less than) The < (less than) operator asks whether the first condition is less than the second condition. Logical Operators
Operator: && (double ampersand) The && (double ampersand) operator asks whether the first condition is true, and additionally whether the second condition is true.
Operator: || (double vertical bar) The || (double vertical bar) operator asks whether the first condition is true, or if the second condition is true. If the first condition is true, the second condition is not evaluated. It does not matter which condition is true
Operator: ! (Exclamation point) The ! (exclamation mark) operator negates the expression to which it is applied. It is equivalent to the "not" keyword.
Bitwise Operators
Operator: & (ampersand) The & (ampersand) bitwise operator compares each bit of its first operand to the corresponding bit of its second operand. If both bits are 1, the corresponding result bit is set to 1. Otherwise, the corresponding result bit is set to 0.
The best example of how to use this operator is in the NewTextEvent function in default.jss. In this function, it is used for a binary comparison of two binary numerical values. The value of nAttibutes is a multiple digit binary numerical value that indicates all the attributes applying to the buffer string. Each attribute is indicated by whether a certain bit in the byte is turned on. The & operator returns all values that exist in both numerical values. For example, if the value of nAttributes is 01001010, then the seventh bit in the result byte of nAttributes & ATTRIB_HIGHLIGHT is set to 1 (ATTRIB_HIGHLIGHT = 64 or 01000000 binary). The second bit in the result byte of nAttributes & ATTRIB_BOLD is set to 1 (ATTRIB_BOLD = 2 or 00000010 binary). The fourth bit in the result byte of nAttributes & ATTRIB_UNDERLINE is set to 1 (ATTRIB_UNDERLINE = 8 or 00001000 binary). But the third bit in the result byte of nAttributes & ATTRIB_ITALIC is set to 0 since ATTRIB_ITALIC is 4 or 00000100 binary and the third bit in the nAttributes byte is 0.
Operator: | (vertical bar) The | (bitwise vertical bar) operator compares each bit of its first operand to the corresponding bit of its second operand. If either bit is 1, the corresponding result bit is set to 1. Otherwise, the corresponding result bit is set to 0.
This operator does a bit-by-bit comparison of two numerical values which is similar to that of the & operator. For example, the statement 00100110 | 11000000 returns 11100110.
Operator: ~(tilde) Use the ~(tilde) operator with & and | (the "and" and "vertical bar") bitwise operators to mask off or exclude a bit from being processed. A good example is in default.jss in the ObjStateChangedEvent function in the following statement:
IndicateControlState(iObjType,nState& (CTRL_CHECKED|CTRL_UNCHECKED))
The statement ensures that if the control is partially checked, the unchecked and checked states are not processed and therefore not indicated by JAWS.
Operator: << (less than less than) Bitwise left shift. Use to shift the bits in a bitwise pattern left. Often, this is done to move a bit to a specific position in a bit set before performing some other bitwise operation.
Operator >> (greater than greater than) Bitwise right shift. Use to shift the bits in a bitwise pattern right. Often, this is done to move a bit to a specific position in a bit set before performing some other bitwise operation.
Miscellaneous Operators
Operator: = (equals) Use this operator to assign a value to a variable.
Operator: . (dot) Use the dot operator to assign or retrieve the name of an item in a collection when the name of the item is known. For example, you can use Months.January to access the item called January in the Months collection. But you may not use The dot operator to access the name of the item if the name of the item is enclosed in quotes, contained in a variable, or is returned by a function call.
Version: This operator is available as of JAWS 11.
Operator: New Use the New operator to create an instance of an array of collection. You must specify the size and dimensions of the array when creating a new array and when creating an instance of the array.
Version: This operator is available as of JAWS 11.
Operator: [] (left bracket, right bracket) Use brackets to specify the size of an array when creating the array . Also, you may use them to access elements of an array. If the array is multi-dimensional, you must separate the index for each dimension by commas. For example, [3,5] specifies the element on the third row and fifth column of the array.
Additionally, use brackets to assign or retrieve the name of an item in a collection if the name of the item is enclosed in quotes, contained in a variable, or is returned by a function call.
Version: This operator is available as of JAWS 11.
Operator: () (left-parenthesis right-parenthesis)
Use to enclose a parameter list for a function call, or to establish order of precedence.