digit> ( ch -- n )

Vocabulary

math.parser

Inputs

ch	a character

Outputs

n	an integer

Word description

Converts a character representation of a digit to an integer.

Notes

This is one of the factors of string>number.

Definition

USING: combinators kernel math ;

IN: math.parser

: digit> ( ch -- n )
    {
        { [ dup 57 <= ] [ 48 - dup 0 < [ drop 255 ] when ] }
        {
            [ dup 97 < ]
            [ 65 10 - - dup 10 < [ drop 255 ] when ]
        }
        [ 97 10 - - dup 10 < [ drop 255 ] when ]
    } cond ; inline