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# Error: $compile:iscp
Invalid Isolate Scope Definition

    Invalid {3} for directive '{0}'. Definition: {... {1}: '{2}' ...}

## Description

When declaring isolate scope the scope definition object must be in specific format which starts with mode character (`@&=<`), after which comes an optional `?`, and it ends with an optional local name.

    myModule.directive('directiveName', function factory() {
      return {
        ...
        scope: {
          'localName': '@', // OK
          'localName2': '&attr', // OK
          'localName3': '<?attr', // OK
          'localName4': ' = attr', // OK
          'localName5': ' =*attr', // OK
          'localName6': 'attr',    // ERROR: missing mode @&=<
          'localName7': 'attr=',   // ERROR: must be prefixed with @&=<
          'localName8': '=attr?',  // ERROR: ? must come directly after the mode
          'localName9': '<*'  // ERROR: * is only valid with =
        }
        ...
      }
    });

Please refer to the `scope` option of the directive definition documentation to learn more about the API.