Option Base

FreeBASIC

Option Base
 
Specifies a default lower bound for array declarations

Syntax

Option Base base_subscript

Parameters

base_subscript
an numeric literal value

Description

Option Base is a statement that sets the default lower bound for any following array declarations. This default remains in effect for the rest of the module in which Option Base is used, and can be overridden by declaring arrays with an explicit lower bound, or with another Option Base statement.

Note: initially, the default base is 0.

Example

'' Compile with the "-lang qb" or "-lang fblite" compiler switches

#lang "fblite"

Dim foo(10) As Integer      ' declares an array with indices 0-10

Option Base 5

Dim bar(15) As Integer      ' declares an array with indices 5-15
Dim baz(0 To 4) As Integer  ' declares an array with indices 0-4


Dialect Differences

  • Only available in the -lang fblite and -lang qb dialects.
  • In -lang fb, Option Base is not allowed, and the default lower bound is always 0.

Differences from QB

  • QBASIC only supported values of 0 or 1 for base_subscript.
  • In QBASIC the word Base was a reserved keyword, and couldn't be used as a variable name.
  • Arrays must always be explicitly created in FreeBASIC. QBASIC would implicitly create an array from base_subscript to 10 if one was used in code without being predefined.

See also