The proposed addition does not go into the mechanism (the names of the specific environment variables or the PowerShell parameters) but is more express about in what manner the behaviour of the installation scripts can be changed.
Introduces that important flexibility as the first topic under 'More on installation'.
Explains that the PowerShell script finally (by default) runs the script for Unix-like operating systems (so a Windows user understands better that the environment variables in the former are applicable to both, and what is meant by the 'final' bootstrap script in the content of the Windows parameters).
Refers to what has gone before, under 'Continuous integration', rather than repeat the added content.
This is a major refactor of some CLI code. We try to distinguish
GHC versions from other versions, so that we can use distinct parsers.
Hopefully this doesn't introduce new bugs.
This also forces ghcup run to use the new internal ~/.ghcup/tmp dir.
1. short hashes now work
2. print the long hash in addition to the detected cabal version of HLS
3. add `--git-describe-version` switch as an alternative to
`--overwrite-version`
Fix 1. and 2. for GHC as well.
A one word tweak to weaken the language in the initial explanation
to make it "less scary": in general ghcup does not always download
all of ghcup, ghc, cabal, stack, and hls
(unless requested or they are not already installed, etc),
but "will download" sounds like the user is has no choice here
except to always download everything,
which might give them second thoughts about trying this script
and hence adopting ghcup.
Perhaps the wording could be made further more precise,
but at least "can" gives one less anxiety.
