Hasklig support for haskell layer

[Profpatsch]

Hasklig is a nice derivation of Source Code Pro that supports ligatures. Someone already found a working solution for integration in Emacs, which I integrated in my config by setting this:

  ;;;; nice glyphs for haskell
  (custom-set-variables '(haskell-font-lock-symbols t)
                        '(haskell-font-lock-symbols-alist
                          (and (fboundp 'decode-char)
                              (list (cons "&&" (decode-char 'ucs #XE100))
                                    (cons "***" (decode-char 'ucs #XE101))
                                    (cons "*>" (decode-char 'ucs #XE102))
                                    (cons "\\\\" (decode-char 'ucs #XE103))
                                    (cons "||" (decode-char 'ucs #XE104))
                                    (cons "|>" (decode-char 'ucs #XE105))
                                    (cons "::" (decode-char 'ucs #XE106))
                                    (cons "==" (decode-char 'ucs #XE107))
                                    (cons "===" (decode-char 'ucs #XE108))
                                    (cons "==>" (decode-char 'ucs #XE109))
                                    (cons "=>" (decode-char 'ucs #XE10A))
                                    (cons "=<<" (decode-char 'ucs #XE10B))
                                    (cons "!!" (decode-char 'ucs #XE10C))
                                    (cons ">>" (decode-char 'ucs #XE10D))
                                    (cons ">>=" (decode-char 'ucs #XE10E))
                                    (cons ">>>" (decode-char 'ucs #XE10F))
                                    (cons ">>-" (decode-char 'ucs #XE110))
                                    (cons ">-" (decode-char 'ucs #XE111))
                                    (cons "->" (decode-char 'ucs #XE112))
                                    (cons "-<" (decode-char 'ucs #XE113))
                                    (cons "-<<" (decode-char 'ucs #XE114))
                                    (cons "<*" (decode-char 'ucs #XE115))
                                    (cons "<*>" (decode-char 'ucs #XE116))
                                    (cons "<|" (decode-char 'ucs #XE117))
                                    (cons "<|>" (decode-char 'ucs #XE118))
                                    (cons "<$>" (decode-char 'ucs #XE119))
                                    (cons "<>" (decode-char 'ucs #XE11A))
                                    (cons "<-" (decode-char 'ucs #XE11B))
                                    (cons "<<" (decode-char 'ucs #XE11C))
                                    (cons "<<<" (decode-char 'ucs #XE11D))
                                    (cons "<+>" (decode-char 'ucs #XE11E))
                                    (cons ".." (decode-char 'ucs #XE11F))
                                    (cons "..." (decode-char 'ucs #XE120))
                                    (cons "++" (decode-char 'ucs #XE121))
                                    (cons "+++" (decode-char 'ucs #XE122))
                                    (cons "/=" (decode-char 'ucs #XE123))))))

It should be easy to provide support in Haskell mode.

[meditans]

On which OS are you, @Profpatsch? Adding this to my spacemacs on Fedora displays some very weird characters, like a dotted arrow pointing right-up for the common arrow ->.

EDIT: my bad, this configuration works very well. +1 for spacemacs inclusion!

[meditans]

As much as I loved this integration, it has some problems: the overlay changes the column numbering, so when querying, for example, intero for types, the types turn up to be incorrect. See for example this issue I incorrectly opened for intero.

Is there something that could be done to correct this, @Profpatsch, @TheBB?

[Profpatsch]

No idea, I don’t use column numbering. Emacs font handling sucks, though.

[Profpatsch]

Okay, with a more recent version of Hasklig the emacs integration broke horribly, but I got it working again: i-tu/Hasklig#84 (comment)

This should be general enough to make it work for multiple similar fonts (e.g. https://github.com/be5invis/Iosevka or https://github.com/tonsky/FiraCode)

[minad]

See https://github.com/minad/hasklig-mode. Support for Fira could be added too (#6972).

[github-actions]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Please let us know if this issue is still valid!

[Profpatsch]

I’m probably not going to write the mode, but we should leave the issue open if somebody else wants to tackle it.

Companion issue for FiraCode: #6972

[github-actions]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Please let us know if this issue is still valid!

[lebensterben]

Closing since this seems to be out of our scope.

P.S. One can use https://wiki.haskell.org/Unicode-symbols for real unicode symbols.