Hi, I hope this is the right place to bring this up. I could not find any 
discussions on this other than the document I quote.

Quick intro: characters with the property Bidi_Mirrored=Yes will be visually 
mirrored within RTL text, such as Hebrew or Arabic. An easy example is the 
Greater Than symbol: A>B and א>ב.

Arrow characters do not have this property: A→B but א→ב.

I've found this discrepancy mentioned in this document:

https://www.unicode.org/L2/L2022/22026r-non-bidi-mirroring.pdf

> In particular, arrow and arrow-like characters
> each often has a mirror character. One could
> argue that they should have had the
> Bidi_Mirrored=Yes property value, but they
> don’t, and cannot now get that.

Even if it weren't for Unicode's stability policies, there are two distinct 
usages of arrow symbols:

To indicate directions, e.g. "Turn left (←) and then right (→)" - in this case 
the arrow refers to the physical direction and should not be mirrored in RTL. 
The existing arrow characters serve this purpose well: "פנה שמאלה (←) ואז ימינה 
(→)‏"

As an operator: "Convert A->B and assign C<-D" - in this case the arrow 
direction should be mirrored if it appears in RTL text. Currently this can only 
be emulated with ASCII "->" as I've just demonstrated. Result: "המר א->ב וקבע 
ג<-ד".

Therefore I think there should be new characters, "Forward Arrow" and "Backward 
Arrow", to serve the latter case. They would use the same glyphs as existing 
arrows, but have the Bidi_Mirrored=Yes property.

Please let me know if this is likely to happen, and what I would have to do to 
make a proper proposal. And if any of you are convinced enough that you would 
like to make a proposal on my behalf, you are welcome to do so!

The same reasoning can be applied to many other characters besides these basic 
arrows. At minimum, all arrow and arrow-like characters should be included. I 
haven't made a thorough search to find all affected characters, at least not 
yet.

Note that some software, such as the Discourse forum software, convert "->" to 
"→" in user content, obviously unaware of this issue. These proposed 
bidi-mirrored arrow characters would be an appropriate replacement in such 
cases. Today, that simple search-and-replace must be replaced with parsing the 
text using the full Unicode Bidi algorithm to select the correct arrow, and 
even then some cases would be impossible to determine without knowing the base 
direction or more context which is not always available.

Awaiting your comments.

Thanks,
Nitai


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