(mutually exclusive options) to allow the dataset reading to end upon
encountering certain text pattern (or a more complicated match, if we
specify a function for the option value).
These options can be used to work with the `maxcount' option; the shortest
of the two (maxcount records read first, or end/last_line_match finds a
match) will end the reading of the dataset.
implemented as a generator rather than yielding the list right away.
This is used mainly in loops, where we don't want to generate all the
elements due to memory concerns.
potential confusion.
* Detail of the important changes:
1) by default now the function's local variables are not included in the
lookup chain. Use _localvars_ flag if you insist on doing that; but
be aware of the caveat (see Parameters' documentation).
2) the default _kwparam_ and _userparam_ names are now passed on to the
child Parameters object instead of the override values given through
the _create_ function argument.
Rationale: To begin with, the default names defined during the creation
of the parent Parameters object should be used by *all* the relevant
functions.
Overrides should be regarded as exceptional rather than common cases.
3) Value overrides (_kwparam_, _userparam_, etc.) in _create_ must now
be specified in keyword=value manner rather than as positional argument.
Rationale: Those overrides must be made conspicuous.
The keyword=value approach also makes the code more resilient to minor
API changes.
All unnamed parameters are supposed to be low-priority defaults.
* Add simple checks for _p, _opts_ default arguments in case they are not
indexable/dict-like objects. This is needed to avoid bizzare error messages
later then the Parameters object is in use.
mode detection (plain python, `python -i', and ipython supported),
and my canned initialization for interactive python environment
(like MYSELF, ARGV).
"next()" method dispatcher is called.
This approach should get rid of the problem with circular reference which
causes the text_input instance not be erasable because of strong reference
to `self' in `self.next.im_self'.
in space-seprated string format.
The output is mainly for human consumption, not for machine re-reading
(although it is possible to do so, in general).