JSLint (prior to version 2013-03-18) will throw the "ADsafe violation: '{a}'" error in a number of situations, but only when the adsafe option is set to true (it's false by default). For more information on ADsafe, see the ADsafe website. Following is a list of potential causes of this error.
The use of a variable statement in the global execution context:
The use of this in ADsafe code:
The use of the arguments object in ADsafe code:
The use of the eval function in ADsafe code:
This error is raised when JSLint encounters code that violates the rules of the ADsafe subset of JavaScript. It is a fatal error that signifies a severe problem with ADsafe code and will have to be fixed before your ADsafe code will execute.
In a commit on 20th March 2013, HTML, CSS and ADsafe parsing functionality was removed from JSLint. If you rely upon this functionality, you will be unable to upgrade JSLint to a version beyond that date.