combining marks for currency characters? general combining character?

[Asmus Freytag (c)]

On 8/3/2016 12:26 PM, Kim Slawson wrote:
> It's nice to see a good selection of currency symbols defined in 
> unicode, but I wonder if it might be useful to add a few combining 
> marks for the purpose of constructing currency symbols.
>
> For example, many currency symbols use single or double horizontal 
> lines, vertical lines or solidi ( |, -, /, ||, =, // ). Having these 
> available as combining marks would simplify the creation of new 
> currency symbols, as many are simply overstruck letters.

Unicode's policy is to disregard combining marks for overlays (as 
opposed to other categories of combining marks) and code the relevant 
combined glyph anyway. That goes for letters that are members for 
alphabets and is done for a number of reasons that all equally well 
apply to currency symbols. So, the short answer is that even with many 
overly marks already defined, these would be disregarded as would any 
additional ones.

They are generically useful in some cases, such as to indicate negation 
for arbitrary mathematical symbols and the like, but not to compose 
letterlike glyphs.

A./