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Static

Defines variables, objects and arrays having static storage

Syntax

Static symbol1 [ (array-dimensions) ] As DataType [ = expression] [, symbol2 [ (array-dimensions) ] As DataType [ = expression], ...]
Static As DataType symbol1 [ (array-dimensions) ] [ = expression] [, symbol2 [ (array-dimensions) ] [ = expression], ...]
Static Var symbol1 = expression [, symbol2 = expression, ...]
Sub|Function procedurename ( parameters ) [[ ByRef ] As DataType] Static
...
End Sub|Function

Parameters

• symbol
• array-dimensions
• lower-bound To upper-bound [, ...] or Any [, Any...] or empty. expression

Description

Specifies static storage for variables, objects and arrays; they are allocated at program startup and deallocated upon exit. Objects are constructed once when they are defined, and destructed upon program exit.

When declaring static arrays, only numeric literals, Constants or Enumerations may be used as subscript range values. Static variable-length arrays must be declared empty (no subscript range list) and resized using ReDim before used.

In both iterative and recursive blocks, like looping control flow statements or procedures, static variables, objects and arrays local to the block are guaranteed to occupy the same storage across all instantiations of the block. For example, procedures that call themselves - either directly or indirectly - share the same instances of their local static variables.

A static variable may only be initialised with a constant value: its starting value is set at the start of the program before any code is run, and so it cannot depend on any variables or functions in it.

When used at procedure definition level (forbidden at declaration line level), Static specifies static storage for all local variables, objects and arrays, except temporary types and internal variables (objects not explicitly declared).

At module-level variable declaration only, the modifier Shared may be used with the keyword Static to make module-level static variables visible inside procedures.

When used with in a user-defined type, Static creates Static Member Procedures Or Variables.

Remarks

Dialect Differences

• Variables cannot be initialised in the -lang qb dialect.

Differences from QB

• QuickBASIC allows variables and arrays to be declared using the Static keyword within procedures and DEF FN routines only. Static forces local visibility of variables and arrays in QuickBASIC DEF FN routines. FreeBASIC supports neither DEF FN routines nor this usage of Static.

See also

• Static (Member)
• Dim, ReDim
• Shared
• Byref (Variables)
• Sub (Module), Function (Module)
• Sub (Member), Function (Member)
• Option Static

Examples

Sub f

    '' times called is initially 0

    Static timesCalled As Integer = 0

    timesCalled += 1

    Print "Number of times called: " & timesCalled

End Sub

'' the static variable in f() retains its value between

'' multiple procedure calls.

f()

f()

Will output:

Number of times called: 1
Number of times called: 2

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Category: Variable Declarations
Kind: keyword

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Reproduced from the FreeBASIC Wiki Manual under the GNU Free Documentation License 1.3 — with no Invariant Sections, no Front-Cover Texts and no Back-Cover Texts. Copyright © the FreeBASIC project and wiki contributors. See License.