There's now a more sensible hierarchy of locations that Cryptol uses to
look for modules. By default, in order it looks for libraries in:
1. The directories specified in the CRYPTOLPATH environment variable
2. The current directory
3. The user data directory (something like `$HOME/.cryptol`)
4. Relative to the executable's install directory
5. The static path used when building the executable (cabal's data-dir)
There is also a new command-line flag for the interpreter:
`--cryptolpath-only` which makes the interpreter ignore locations 2-5.
This commit also reworks the Makefile and build/release process. These
are bunched together because they play off each other quite a bit; the
build/release process determines the location of the `Cryptol.cry`,
which must be found when looking for modules.
Rather than leaning on `cabal install`, we now use a combination of
`cabal configure`, `cabal build`, and `cabal copy`. A couple of upshots
to this:
- More of the release staging is handled by cabal -- we don't have to go
in and manually copy things out of the sandbox. In fact, the `cryptol`
executable never goes into the sandbox.
- The testing infrastructure runs on executables that are in place in
the staging directory, rather than in the sandbox. This should be more
hygienic and realistic.
- The `Cryptol.cry` prelude file is now in `/share/cryptol` in order to
better reflect the common POSIX structure. This means Cryptol will
play nicer in global installs, and mirrors what other interpreted
languages do.
- The default build settings use a prefix of `/usr/local` rather than
using the sandbox directory. This makes them more relocatable for
binary distributions. Set PREFIX= before making to change this.
The python side of the notebook needed to be updated to expect a
.cabal-sandbox rather than cabal-dev sandbox. Also added a -fnotebook
flag to the cabal file to build the Haskell side of it.
