Difference between revisions of "Unicode-symbols"

Revision as of 13:03, 23 March 2010

Overview

An overview of the packages that provide Unicode symbols.

Naming: A package X-unicode-symbols defines new symbols for functions and operators from the package X.

All symbols are documented with their actual definition and information regarding their Unicode code point. They should be completely interchangeable with their definitions.

Alternatives for existing operators have the same fixity. New operators will have a suitable fixity defined.

UnicodeSyntax

GHC offers the UnicodeSyntax language extension. If you decide to use Unicode in your Haskell source then this extension can greatly improve how it looks.

base-unicode-symbols

Extra symbols for the base package.

 API docs: http://hackage.haskell.org/package/base-unicode-symbols

 darcs get http://code.haskell.org/~roelvandijk/code/base-unicode-symbols

====New symbol ideas==== (please add your own)

Original	Symbol	Code point	Name
Control.Monad.>>	≫	U+226B	MUCH GREATER-THAN

containers-unicode-symbols

Extra symbols for the containers package.

 API docs: http://hackage.haskell.org/package/containers-unicode-symbols

 darcs get http://code.haskell.org/~roelvandijk/code/containers-unicode-symbols

Fixities

What should the fixities for the following symbols be?

Symbol	Code point	Name
∪	U+222A	UNION
∩	U+2229	INTERSECTION
⊆	U+2286	SUBSET OF OR EQUAL TO
⊇	U+2287	SUPERSET OF OR EQUAL TO
⊈	U+2288	NEITHER A SUBSET OF NOR EQUAL TO
⊉	U+2289	NEITHER A SUPERSET OF NOR EQUAL TO
⊂	U+2282	SUBSET OF
⊃	U+2283	SUPERSET OF
⊄	U+2284	NOT A SUBSET OF
⊅	U+2285	NOT A SUPERSET OF

Intuitively there is a correspondence with numerical operators. Compare the following operators:

∪	+
⊃	>
⊄	≮

Likewise you would like similar associativities and precedence levels:

  x + y + z < w == ((x + y) + z) < w
  x ∪ y ∪ w ⊂ z == ((x ∪ y) ∪ z) ⊂ w

====New symbol ideas==== (please add your own)

Input methods

These symbols are all very nice but how do you type them?

(please add info for other editors)

Emacs

Direct

Enter symbols directly: C-x 8 RET, then type either the character's name or its hexadecimal code point.

Custom script

 http://code.haskell.org/~roelvandijk/code/emacs-unicode-symbols

In your .emacs file:

(load "~/elisp/emacs-unicode-symbols/haskell-symbols") (defun haskell-unicode () (local-set-key (kbd "C-M-u") 'replace-haskell-unicode)) (add-hook 'haskell-mode-hook 'haskell-unicode)

With above hook installed navigate the point to right after a normal symbol like -> and press C-M-u to transform it into a beautiful →.

Caveat: The author is an absolute Lisp newbie. Patches to above script are more than welcome.

Abbrev mode

The Abbrev mode is not suitable since it only deals with words, not operators.

Agda

Use Agda's input method.

@@ Line 14: / Line 14: @@
 GHC offers the [http://www.haskell.org/ghc/docs/latest/html/users_guide/syntax-extns.html#unicode-syntax UnicodeSyntax] language extension. If you decide to use Unicode in your Haskell source then this extension can greatly improve how it looks.
-==== Input methods ====
-These symbols are all very nice but how do you type them?
-TODO
 == base-unicode-symbols ==
@@ Line 25: / Line 19: @@
 Extra symbols for the [http://hackage.haskell.org/package/base base] package.
-API docs: http://hackage.haskell.org/package/base-unicode-symbols
+  API docs: http://hackage.haskell.org/package/base-unicode-symbols
-darcs get http://code.haskell.org/~roelvandijk/code/base-unicode-symbols
+  darcs get http://code.haskell.org/~roelvandijk/code/base-unicode-symbols
-====New symbol ideas==== (please add your own)
+====New symbol ideas==== (''please add your own'')
 {| class="wikitable" border="1"
 |-
@@ Line 47: / Line 41: @@
 Extra symbols for the [http://hackage.haskell.org/package/containers containers] package.
-API docs: http://hackage.haskell.org/package/containers-unicode-symbols
+  API docs: http://hackage.haskell.org/package/containers-unicode-symbols
-darcs get http://code.haskell.org/~roelvandijk/code/containers-unicode-symbols
+  darcs get http://code.haskell.org/~roelvandijk/code/containers-unicode-symbols
 ==== Fixities ====
@@ Line 61: / Line 55: @@
 !  Name
 |-
-|  &#x222A;
+|  &cup;
 |  U+222A
 |  UNION
 |-
-|  &#x2229;
+|  &cap;
 |  U+2229
 |  INTERSECTION
 |-
-|  &#x2286;
+|  &sube;
 |  U+2286
 |  SUBSET OF OR EQUAL TO
 |-
-|  &#x2287;
+|  &supe;
 |  U+2287
 |  SUPERSET OF OR EQUAL TO
@@ Line 85: / Line 79: @@
 |  NEITHER A SUPERSET OF NOR EQUAL TO
 |-
-|  &#x2282;
+|  &sub;
 |  U+2282
 |  SUBSET OF
 |-
-|  &#x2283;
+|  &sup;
 |  U+2283
 |  SUPERSET OF
@@ Line 117: / Line 111: @@
 Likewise you would like similar associativities and precedence levels:
-<tt>
+<haskell>
   x + y + z < w == ((x + y) + z) < w
-  x &#x222A; y &#x222A; w &#x2282; z == ((x &#x222A; y) &#x222A; z) &#x2282; w
+  x ∪ y ∪ w ⊂ z == ((x ∪ y) ∪ z) ⊂ w
+</haskell>
+====New symbol ideas==== (''please add your own'')
+== Input methods ==
+These symbols are all very nice but how do you type them?
+(''please add info for other editors'')
+=== Emacs ===
+'''Direct'''
+Enter symbols directly: <tt>[http://www.gnu.org/software/emacs/manual/html_node/emacs/International-Chars.html C-x 8 RET]</tt>, then type either the character's name or its hexadecimal code point.
+'''Custom script'''
+  http://code.haskell.org/~roelvandijk/code/emacs-unicode-symbols
+In your .emacs file:
+<tt>
+  (load "~/elisp/emacs-unicode-symbols/haskell-symbols")
+  (defun haskell-unicode () (local-set-key (kbd "C-M-u") 'replace-haskell-unicode))
+  (add-hook 'haskell-mode-hook 'haskell-unicode)
 </tt>
+With above hook installed navigate the point to right after a normal symbol like '''->''' and press '''<tt>C-M-u</tt>''' to transform it into a beautiful '''&rarr;'''.
-====New symbol ideas==== (please add your own)
+''Caveat'': The author is an absolute Lisp newbie. Patches to above script are more than welcome.
+'''Abbrev mode'''
+The [http://www.gnu.org/software/emacs/manual/html_node/emacs/Abbrevs.html Abbrev mode] is not suitable since it only deals with ''words'', not ''operators''.
+'''Agda'''
+Use Agda's [http://wiki.portal.chalmers.se/agda/pmwiki.php?n=Docs.UnicodeInput input method].