Shell Configuration on tcsh

[GarrettAlbright]

Yes, some of us still use it. GET OFF MY LAWN

$ echo 'setenv SWIFTENV_ROOT "$HOME/.swiftenv"' >> ~/.tcshrc
$ echo 'setenv PATH "$SWIFTENV_ROOT/bin:$PATH"' >> ~/.tcshrc
$ echo 'eval "`swiftenv init - | sed -e \'s/export PATH=/setenv PATH /\'`"' >> ~/.tcshrc

[kylef]

@GarrettAlbright Does this all work for you? I have never used tcsh. If it's working for you feel free to add this to the docs at https://github.com/kylef/swiftenv/blob/master/docs/installation.md.

I wonder if we can test using swiftenv with each shell on CI somehow, I'll take a look.

[kylef]

Added a simple test for fish in ec53cc2 so can do something similiar for tcsh to validate that installation + shims work correctly on CI.