{{DISPLAYTITLE:OPTION _EXPLICIT}}  
[[OPTION _EXPLICIT]] instructs the compiler to require variable declaration with [[DIM]], [[REDIM]] or an equivalent statement.


{{PageSyntax}}
: [[OPTION _EXPLICIT]]


{{PageDescription}}
* With [[OPTION _EXPLICIT]] you can avoid typos by having QB64 immediately warn in the '''Status area''' of new variables used without previous declaration.
* Enable [[OPTION _EXPLICIT]] temporarily even if a program source file doesn't contain the directive by specifying the '''-e''' switch when compiling via command line (''qb64 -c file.bas -e'').


{{PageErrors}}
* If used, [[OPTION _EXPLICIT]] must be the very first statement in your program. No other statements can precede it (except for [[$NOPREFIX]] or comment lines started with an [[Apostrophe|apostrophe]] or [[REM]]).
* Do not use [[OPTION _EXPLICIT]] in [[$INCLUDE]]d modules.


{{PageExamples}}
''Example:'' Avoiding simple typos with [[OPTION _EXPLICIT]] results shown in the QB64 IDE Status area.
{{CodeStart}}{{Cl|OPTION _EXPLICIT}}

{{Cl|DIM}} myVariable {{Cl|AS}} {{Cl|INTEGER}}

myVariable = 5

{{Cl|PRINT}} myVariabe
{{CodeEnd}}

''QB64 IDE Status will show:''
'''Variable 'myVariabe' (SINGLE) not defined on line 4'''


{{PageSeeAlso}}
* [[OPTION _EXPLICITARRAY]]
* [[DIM]], [[REDIM]]
* [[SHARED]]
* [[STATIC]]


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