Range patterns

In patterns, Caml Light recognizes the form ` c ` .. ` d ` (two character constants separated by ..) as a shorthand for the pattern

` c ` | ` c₁ ` | ` c₂ ` |...| ` c_n ` | ` d `

where c_1, c_2, ..., c_n are the characters that occur between c and d in the ASCII character set. For instance, the pattern `0`..`9` matches all characters that are digits.