Bidirectional structured text

@aphillips @r12a @matial the use cases described in the current document (formats based on JSON, WebIDL, and other non-markup data languages) and best practices developed to provide a solution for such use cases ring the bells for me. @matial and myself have been tackling a slightly more general (a higher level if you wish) formatting problem uniquely associated with bidirectional scripts (i.e. Arabic / Hebrew). We coined a term: "structured text problem" in order to describe it.

Conceptually any kind of structure starting from simplest concatenation like Author: Mark Twain and ending with as complex as regular expression or Java code, falls in the same category of structured text as long as it includes bidirectional text.

I list here several broad categories of structured text:

Simplest structure

• Date / time stamps (4 Oct 2018)
• File path (c:\root\folder\file.txt)
• Breadcrumb (first -> second -> third)
• Concatenations (a(b), a-b, a:b ets.)

Moderate structure + a lot of political exposure

• URL
• Email address

Complex structure

• Math formulas
• Regular Expressions
• Programming language (SQL query, Java, C, C++ ...)
• Markup editor (HTML, XML etc.)

In all cases above it is not enough to just specify for specific piece of text in which direction it should be displayed. In addition:

• It is necessary to enforce the syntax ( which makes the expression readable) and which without any additional work won't be enforced in general case by UBA alone.
• It is necessary to specific and enforce display rules - in some Arabic countries math formulas run from left to right, while in others they run from right to left.

The latest document authored by @matial and myself proposing a general approach for tackling structured text problem is available from: https://docs.google.com/document/d/1y9LhT7rbGGVHjh2uqTAYHzN5PfbAkPxO5sMJygOPc3I/edit#heading=h.b43z973xff51

Do you believe it makes sense to extend the scope of your document and touch the subject of structured text ? Alternatively, would you agree to participate in a work on additional document dedicated to that subject ?

PS. Even though this specific article is not talking about specific implementation for problem solution (and thus at least in my eyes it means that this not in the scope for this article), I do wish to mention that at least for me the subject is at the very least 10 years long. During those years many solutions were implemented in different technologies (both properietary to IBM and open source such as Eclipse / ICU / Dojo etc. ).

Read the current document and the linked Google document to understand the proposed structured-text scope and existing best practices. Done would require a maintainer decision on whether to expand the document or create a separate document for bidirectional structured text; the issue names no implementation files or tests.