expression manipulation - How to Clear variables represented as a list of strings?

Say I have a string list called fullpara

fullpara={"width", "long", "line", "distance"}

And there are corresponding variables to each string, and I want to Clear these variables

Clear[width, long, line, distance]

How to do it in a way to manipulate fullpara as a whole?

Clear@@(ToExpression/@fullpara)

obviously won't work because ToExpression will evaluate the variable that already has a value.

Answer

According to the documentation of Clear or ClearAll it is possible to provide symbols in form of regular expression (limited), in particular as string with exact symbol name.

Clear @@ {"width", "long", "line", "distance"}

Let's say there is no possibility to do that, one way would be:

Map[Clear, 
    ToExpression[{"width", "long", "line", "distance"}, InputForm, Hold], 
    {2}]; // ReleaseHold

Comments

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