Allow unicode sub/superscript symbols in operators
While #4373 (closed) permits
Prelude> let v₁ = 1the following is rejected
Prelude> let m >>=₁ f = undefined
<interactive>:0:10: lexical error at character '\8321'Identifiers with non-numeric subscripts are not accepted either:
Prelude> let vₐ = 1
<interactive>:0:6: lexical error at character '\8336'I wrote a small patch that makes such definitions possible.
- A new unicode Alex macro,
$subsup, is introduced and added to$idchar,$symchar, and$graphic - A unicode code point is classified as
$subsupbyalexGetChariff either of the following holds:
a. The code point is annotated with <sub> or <super> in http://www.unicode.org/Public/UNIDATA/UnicodeData.txt
b. It is the [DOUBLE/TRIPLE/QUADRUPLE] PRIME (U+2032, U+2033, U+2034, U+2057)
Trac metadata
| Trac field | Value |
|---|---|
| Version | 7.1 |
| Type | FeatureRequest |
| TypeOfFailure | OtherFailure |
| Priority | normal |
| Resolution | Unresolved |
| Component | Compiler |
| Test case | |
| Differential revisions | |
| BlockedBy | |
| Related | |
| Blocking | |
| CC | |
| Operating system | |
| Architecture |