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QB64-PE/internal/help/OPTION_BASE.txt

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The {{KW|OPTION BASE}} statement is used to set the default lower bound of arrays.
{{PageSyntax}}
:{{KW|OPTION BASE}} {0|1}
{{PageDescription}}
* This statement affects array declarations where the lower bound of a dimension is not specified.
* When used, {{KW|OPTION BASE}} must be used before any array declarations ({{KW|DIM}}) to be affected.
* By default, the lower bound for arrays is zero, and may be changed to one using the statement.
* Otherwise, arrays will be dimensioned from element 0 if you DIM just the upper bounds.
* You can also set other array boundaries by using {{KW|TO}} in the DIM such as: DIM array(5 TO 10)
* Note: Neither '''OPTION''' nor '''BASE''' can be used as numerical variable names.
''Example 1:'' Set the default lower bound for array declarations to one.
{{CodeStart}}
{{Cl|OPTION BASE}} 1
' Declare a 5-element one-dimensional array with element indexes of one through five.
{{Cl|DIM}} array(5) {{Cl|AS}} {{Cl|INTEGER}}
{{Cl|PRINT}} {{Cl|LBOUND}}(array)
{{CodeEnd}}
{{OutputStart}} 1{{OutputEnd}}
''Example 2:'' Set the default lower bound for array declarations to zero.
{{CodeStart}} '' ''
{{Cl|OPTION BASE}} 0
' Declare an 18-element two-dimensional array with element indexes of zero through two
' for the first dimension, and 10 through 15 for the second dimension.
{{Cl|DIM}} array(2, 10 to 15) {{Cl|AS}} {{Cl|INTEGER}}
{{Cl|PRINT}} {{Cl|LBOUND}}(array, 1)
{{Cl|PRINT}} {{Cl|LBOUND}}(array, 2)
{{CodeEnd}}
{{OutputStart}} 0
10
{{OutputEnd}}
{{PageSeeAlso}}
* {{KW|Arrays}}, {{KW|LBOUND}}, {{KW|UBOUND}}
* {{KW|DIM}}, {{KW|REDIM}}, {{KW|STATIC}}, {{KW|COMMON}}
{{PageNavigation}}