Operator - (Subtract)

FreeBASIC

Operator - (Subtract)
 
Subtracts two expressions

Syntax
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.

Example

Dim n As Single
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