# `•c` — Case

`•c Y` folds case. `1•c Y` converts to upper case, and `¯1•c Y` to lower
case. A character vector converts as text, with Unicode’s full case
mappings: `ß` becomes `SS`, and a `Σ` that ends a word lowercases to
`ς`. Any other character converts on its own, and stays unchanged when
its mapping has more than one character. Folding converts to upper case,
then to lower case. `•c` keeps the argument’s nesting and leaves items
that aren’t characters unchanged.

``` bpl
•c "AbC"           ⍝ "abc"
1•c "AbC"          ⍝ "ABC"
1•c "straße"       ⍝ "STRASSE"
¯1•c "ΟΔΟΣ"        ⍝ "οδος"
```