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* Improved signatures of the **foreach()** decorator and the
**paramseq()** constructor: they take either exactly one positional
argument which must be a test parameter collection (as previously: a
sequence/mapping/set or a **paramseq** instance, or a callable
returning an iterable...), or *any number of positional and/or keyword
arguments* being test parameters (singular parameter values, tuples of
parameter values or **param** instances...). For example,
``foreach([1, 42])`` can now also be spelled as ``foreach(1, 42)``.
* Several tests/documentation-related updates, fixes and improvements.