Add JuliaLang/JuliaSyntax.jl#525 to NEWS.md, flisp parser, and REPL

[pthariensflame]

Now that JuliaLang/JuliaSyntax.jl#525 has been merged, also add it to the flisp parser and REPL, and document it!

[Keno]

Also needs to be added in the flisp parser and needs to wait for the JuliaSyntax version bump.

[pthariensflame]

@Keno @nsajko This PR now also adds support for U+1F8B2 🢲 to the flisp parser and with it the Base id char functions.

[nsajko]

I'm guessing this PR will also need tests, so I added the label.

[pthariensflame]

@nsajko I'm not sure what to test; I can't find any tests for the other arrow operators that already exist.

[nsajko]

I'd write a simple test like this one:

@testset "RIGHTWARDS ARROW WITH LOWER HOOK" begin
    🢲(l, r) = 2l + 3r
    @test 5 === (1 🢲 1)
end

Perhaps also something to test its operator precedence?

Something like this could be fine, too:

julia/test/syntax.jl

Lines 2274 to 2280 in 9a278a2

	# issue 45962
	@testset "binary ⭄, ⥺, ⭃, and ⥷" begin
	@test Meta.parse("a ⭄ b") == Expr(:call, :⭄, :a, :b)
	@test Meta.parse("a ⥺ b") == Expr(:call, :⥺, :a, :b)
	@test Meta.parse("a ⭃ b") == Expr(:call, :⭃, :a, :b)
	@test Meta.parse("a ⥷ b") == Expr(:call, :⥷, :a, :b)
	end

[pthariensflame]

@nsajko Added something based on your second example and the others in that file.

[pthariensflame]

Is this ready to merge or are we still waiting on JuliaLang/JuliaSyntaxHighlighting.jl#9 and its followups?

[pthariensflame]

@Keno Since the branch just happened: is this able to get in for Julia 16 after all, or do we need to undo the JuliaSyntax change that’s already included in 1.0?

[Keno]

It'll be added to the release branch after merge. There's a couple of other PRs in the same boat