Operator - (Subtract)
Subtracts two expressions
Syntax:
declare operator - ( byref lhs as integer, byref rhs as integer ) as integer
declare operator - ( byref lhs as uinteger, byref rhs as uinteger ) as uinteger
declare operator - ( byref lhs as single, byref rhs as single ) as single
declare operator - ( byref lhs as double, byref rhs as double ) as double
declare operator - ( byref lhs as T Pointer, byref rhs as T Pointer ) as integer
declare operator - ( byref lhs as T Pointer, byref rhs as integer ) as T Pointer
declare operator - ( byref lhs as T, byref rhs as T ) as integer
declare operator - ( byref lhs as T, byref rhs as integer ) as T
declare operator - ( byref lhs as integer, byref rhs as T ) as T
declare operator - ( byref lhs as uinteger, byref rhs as uinteger ) as uinteger
declare operator - ( byref lhs as single, byref rhs as single ) as single
declare operator - ( byref lhs as double, byref rhs as double ) as double
declare operator - ( byref lhs as T Pointer, byref rhs as T Pointer ) as integer
declare operator - ( byref lhs as T Pointer, byref rhs as integer ) as T Pointer
declare operator - ( byref lhs as T, byref rhs as T ) as integer
declare operator - ( byref lhs as T, byref rhs as integer ) as T
declare operator - ( byref lhs as integer, byref rhs as T ) as T
Usage:
result = lhs - rhs
Parameters:
lhs
The left-hand side expression to subtract from.
rhs
The right-hand side expression to subtract.
T
Any pointer type.
Return Value:
Returns the subtraction of two expressions.
Description:
When the left and right-hand side expressions are numeric values, Operator - (Subtract) returns the subtraction of the two values.
If the left and right-hand side expressions are both of the T Pointer type, for some type T, the operator performs pointer subtraction on the address, returning the result. This is different from numeric subtraction because the difference is divided by Sizeof( T ).
If an integral value n is subtracted from a T Pointer type, the operator performs pointer arithmetic on the address, returning the memory position of a T value, n indices before (assuming (-n) is within bounds of a contiguous array of T values). This behaves differently from numeric subtraction, because the Integer value is scaled by Sizeof( T ).
Neither operand is modified in any way.
This operator can be overloaded to accept user-defined types.
If the left and right-hand side expressions are both of the T Pointer type, for some type T, the operator performs pointer subtraction on the address, returning the result. This is different from numeric subtraction because the difference is divided by Sizeof( T ).
If an integral value n is subtracted from a T Pointer type, the operator performs pointer arithmetic on the address, returning the memory position of a T value, n indices before (assuming (-n) is within bounds of a contiguous array of T values). This behaves differently from numeric subtraction, because the Integer value is scaled by Sizeof( T ).
Neither operand is modified in any way.
This operator can be overloaded to accept user-defined types.
Examples:
Dim n As Single
n = 4 - 5
Print n
n = 4 - 5
Print n
will produce the output:
-1
Dialect Differences:
- In the -lang qb dialect, this operator cannot be overloaded.
Differences from QB:
- None
See also:
Back to Arithmetic Operators
Back to Operators
