14.8: Hexadecimal

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We cannot finish this chapter without talking about hexadecimal. Pharo uses the same syntax for hexadecimal than for binary. 16rF indicates that F is encoded in 16 base.

We can get the hexadecimal equivalent of a number using the message hex. Using the message printStringHex we get the number printed in hexadecimal without the radix notation.

15 hex
    → '16rF'

15 printStringHex
    → 'F'

16rF printIt
    → 15

The following snippet lists some equivalence between a number and its hexadecimal representation.

{(1->'16r1'). (2->'16r2'). (3->'16r3'). (4->'16r4'). (5->'16r5'). (6->'16r6'). (7->'16r7').
    (8->'16r8'). (9->'16r9'). (10->'16rA'). (11->'16rB'). (12->'16rC'). (13->'16rD').
    (14 ->'16rE'). (15->'16rF')}

When doing bit manipulation it is often shorter to use an hexadecimal notation over a binary one. Even if for bitAnd: the binary notation may be more readable

16rF printStringBase: 2
    → '1111'
2r00101001101 bitAnd: 2r1111
    → 2r1101
2r00101001101 bitAnd: 16rF
    → 2r1101