code-point-length ( n -- x )

Vocabulary

io.encodings.utf8

Inputs

n

an object

Outputs

x

an object

Definition

USING: combinators kernel math math.order ;

IN: io.encodings.utf8

: code-point-length ( n -- x )
    [ 1 ] [
        log2 {
            { [ dup 0 6 between? ] [ 1 ] }
            { [ dup 7 10 between? ] [ 2 ] }
            { [ dup 11 15 between? ] [ 3 ] }
            { [ dup 16 20 between? ] [ 4 ] }
        } cond nip
    ] if-zero ;