If Ascii operators are definable, why not Unicode Symbols?
I'm sure I join many in being glad there's finally a powerful language tied tightly to a mainstream GUI/Database/Communication framework.
I haven't been sure where to post this, but here seems the best spot.
I need to use Unicode symbol characters either as operators or as function names. I'd like syntactic sugar, but I don't need it.
Guy Steele pointed out in Communications of the ACM that "*" was a forced choice when it was adopted from Ascii as multiply, but my software works in Unicode, so I'm not tethered to Ascii anymore.
!$%&*+-./<=>?,@^|~:
Part of localization includes local programmers. Why limit the set of operators that can be defined in F#? It isn't orthogonal to C#'s and F#'s acceptance of many Unicode IsLetter in identifiers.
Also, F# is likely to be used for symbolic manipulation of problems from logic, math, physicists, etc. It makes work much easier if there's a direct mapping into the language of the basic operators. (F# and C# accept many Unicode IsLetter? as well as IsDigit'? This is a request to allow Unicode IsSymbol? As operators with the precedence of, for example, *, or, since “+” is both a unary and binary operator, I could put up with the precedence of + and make up the difference with parenthesized groupings.
Consider the domain-specific needs of logicians, mathematicians, physicists, etc. I'd rather write a symbolic differentiator or integrator using math symbols than Ascii permutations of already-taken operators.
I've written many languages in other languages, but because F# is tightly .Net-integrated, this issue poses special challenges without language support:
It's trivial to cobble up a translator that takes Unicode-operator F# source and maps it, line-by-line, to Ascii-operator F# source.
But when debugging, how do I make sure the programmer still sees their untranslated source? And that they can see variable values.
Operators and converts them is trivial. But how do I ensure the translation is what gets compiled, while the programmer sees their own source? If I map line-for-line correctly, how do I ensure they can still point at a variable and see its value?
There is a math (Unicode) symbol extension for F# available in the Visual Studio Gallery.
This allows you to define Unicode symbols, eg:
let inline (~∑) xs = xs |> Seq.sum
let total = ∑myList
You may be interested in Project Fortress which is a new functional programming language that embraces the Unicode character set (among many other features). In particular, see the Mathematical Syntax in Fortress page which contains some sample code.
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