def valueFromString(self, value, extra=None, db=None):
try:<EOL><INDENT>return projex.text.safe_eval(value)<EOL><DEDENT>except ValueError:<EOL><INDENT>return <NUM_LIT:0><EOL><DEDENT>
Converts the inputted string text to a value that matches the type from
this column type.

:param      value | <str>
            extra | <variant>