Custom Robust eval Function

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 Note: This function can only be used in a Trusted Macro

This user defined function redefines the standard eval() function, allowing it to be given a number, empty string, or JSON object/array and not throw an exception.

Macros

Place both of these macros on the same library token.

1.3b56+


onCampaignLoad

[ defineFunction( "eval", "evalFunction@this", 1, 0 ) ]



evalFunction

//  Error handling
[ assert( argCount() >= 1, "<b>eval()</b> - Invalid number of parameters <i>0</i>,
                            expected at least <i>1</i> parameter.", 0 ) ]

//  Initialise variables
[ X_Expression_X = arg( argCount()-1 ) ]
[ X_CancelEval_X = 0 ]
[ X_TypeTest_X = json.type( X_Expression_X ) ]

//  Handle all numbers
[ if( isNumber( X_Expression_X ) == 1 ), code:
{
   [ X_CancelEval_X = 1 ]
} ]

//  Handle empty strings
[ if( X_TypeTest_X == "UNKNOWN" ), code:
{
    [ if( X_Expression_X == "" ), code:
    {
        [ X_CancelEval_X = 1 ]
    } ]
} ]

//  Handle JSON types
[ if( X_TypeTest_X == "ARRAY" || X_TypeTest_X == "OBJECT" ), code:
{
    [ X_CancelEval_X = 1 ]
} ]

//  Evaluate or cancel, then return
[ if( X_CancelEval_X == 1 ), code:
{
    [ macro.return = X_Expression_X ]
};{
    [ macro.return = oldFunction( X_Expression_X ) ]
} ]