Clarify the difference between collect and bracket notation for generators (#50619)
As a follow-up to my question on the forum [Unclear documentation of
`collect`? (similarity and difference with
brackets)](https://discourse.julialang.org/t/unclear-documentation-of-collect-similarity-and-difference-with-brackets/),
here is a tentative expansion of the docstring of `Base.collect` to
clarify both the similarities and differences with the bracket notation
for generators.
I'm pretty sure it needs so edits, but here are the motivating factors
behind the changes, by decreasing order of importance:
1. avoid the presence of bracket notation in the example without
explanation (in the present docstring, I find it highly *implicit*)
2. simplification of examples to focus on the topic (and not on range
syntax or filtering in comprehensions)
3. avoid wasting vertical space by using longer than needed
iterators/generators
Feedback on my formulation is welcome!
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Co-authored-by: Max Horn <max@quendi.de>
Co-authored-by: Jishnu Bhattacharya <jishnub.github@gmail.com>