IDA Help: eval

Evaluate an expression, in the current scripting language.
     expr - an expression
returns: the expression value.
If there are problems, the returned value will be "IDC_FAILURE: xxx"
where xxx is the error description
Thread-safe function.

string or long eval(string expr);

// Macro to check for evaluation failures:
#define EVAL_FAILURE(code) (value_is_string(code) && substr(code, 0, 13) == "IDC_FAILURE: ")