strings.isLetter() function
The strings.isLetter()
function tests if a single character string is a letter (a-z, A-Z).
*Output data type: Boolean*
import "strings"
strings.isLetter(v: "A")
// returns true
Parameters
v
The single character string to test.
*Data type: String*
Examples
Filter by columns with single-letter values
import "strings"
data
|> filter(fn: (r) => strings.isLetter(v: r.serverRef))