The definition of free type variable

In v1.2 manual, the free type varialbe is defined as “We say that a variable V is free in type
T if T does not contain the UnionAll that introduces variable V.” But in the context, it seems to be “does” instead of “does not”. Is that right?

reference for anyone reading this,

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I think the wording in the manual is correct. If not used in a UnionAll, the variable remains free.

Look at the examples in the manual.

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It is the sample following the definition. But it seems not match. Or the sample is not correct?