[swift-evolution] [Proposal] Refining Identifier and Operator Symbology

[Ben Rimmington]

> On 21 Oct 2016, at 13:42, Benjamin Spratling wrote:
> 
> Brackets and symbols are definitely operators.  Different brackets are used to represent various quantum mechanical forms and operations.

The brackets are mostly "bracket pieces":

	[:Math_Symbol:]
	- [:name=/\bANGLE\b/:]
	- [:Emoji:]
	- [:ID_Continue:]
	- [:NFC_Quick_Check=No:]
	& [:Script_Extensions=Common:]
	& [:Block=Miscellaneous_Technical:]

<http://www.unicode.org/cldr/utility/list-unicodeset.jsp?a=%5B%3AMath_Symbol%3A%5D%0D%0A-+%5B%3Aname%3D%2F%5CbANGLE%5Cb%2F%3A%5D%0D%0A-+%5B%3AEmoji%3A%5D%0D%0A-+%5B%3AID_Continue%3A%5D%0D%0A-+%5B%3ANFC_Quick_Check%3DNo%3A%5D%0D%0A%26+%5B%3AScript_Extensions%3DCommon%3A%5D%0D%0A%26+%5B%3ABlock%3DMiscellaneous_Technical%3A%5D>

> Arrows are also useful as operators, including but not restricted to chemical reactions.

Including arrows, there are 740 operators:

	[:Math_Symbol:]
	- [:name=/\bANGLE\b/:]
	- [:name=EMPTY SET:]
	- [:name=INFINITY:]
	- [:Emoji:]
	- [:ID_Continue:]
	- [:NFC_Quick_Check=No:]
	& [:Script_Extensions=Common:]
	& [[:Block=Arrows:]
	   [:Block=General_Punctuation:]
	   [:Block=Latin_1_Supplement:]
	   [:Block=Mathematical_Operators:]
	   [:Block=Miscellaneous_Mathematical_Symbols_A:]
	   [:Block=Miscellaneous_Symbols_And_Arrows:]
	   [:Block=Supplemental_Arrows_A:]
	   [:Block=Supplemental_Arrows_B:]
	   [:Block=Supplemental_Mathematical_Operators:]]

<http://www.unicode.org/cldr/utility/list-unicodeset.jsp?a=%5B%3AMath_Symbol%3A%5D%0D%0A-+%5B%3Aname%3D%2F%5CbANGLE%5Cb%2F%3A%5D%0D%0A-+%5B%3Aname%3DEMPTY+SET%3A%5D%0D%0A-+%5B%3Aname%3DINFINITY%3A%5D%0D%0A-+%5B%3AEmoji%3A%5D%0D%0A-+%5B%3AID_Continue%3A%5D%0D%0A-+%5B%3ANFC_Quick_Check%3DNo%3A%5D%0D%0A%26+%5B%3AScript_Extensions%3DCommon%3A%5D%0D%0A%26+%5B%5B%3ABlock%3DArrows%3A%5D%0D%0A+++%5B%3ABlock%3DGeneral_Punctuation%3A%5D%0D%0A+++%5B%3ABlock%3DLatin_1_Supplement%3A%5D%0D%0A+++%5B%3ABlock%3DMathematical_Operators%3A%5D%0D%0A+++%5B%3ABlock%3DMiscellaneous_Mathematical_Symbols_A%3A%5D%0D%0A+++%5B%3ABlock%3DMiscellaneous_Symbols_And_Arrows%3A%5D%0D%0A+++%5B%3ABlock%3DSupplemental_Arrows_A%3A%5D%0D%0A+++%5B%3ABlock%3DSupplemental_Arrows_B%3A%5D%0D%0A+++%5B%3ABlock%3DSupplemental_Mathematical_Operators%3A%5D%5D>

-- Ben