seqlings 3.0.7

Interactive exercises for learning Seq, a stack-based programming language
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# Exercise: Hexadecimal Encoding
#
# Hex encoding represents each byte as two hex digits (0-9, a-f).
# Useful for debugging, checksums, and cryptographic output.
#
# encoding.hex-encode ( String -- String )
# encoding.hex-decode ( String -- String Bool )
#
# Example:
#   "Hi" encoding.hex-encode  # "4869"
#   "4869" encoding.hex-decode  # "Hi" true
#
# Note: Decode is case-insensitive (accepts "4869" or "4869")
#
# Your task: Implement hex encoding/decoding
# When done, delete the marker line below.

# I AM NOT DONE

: to-hex ( String -- String )
    # Convert string to hex representation
    # Your code here
;

: from-hex ( String -- String Bool )
    # Convert hex back to string
    # Your code here
    false
;

: test-hex ( -- )
    # Test encoding
    "Hello" to-hex
    # Do not edit below this line
    "48656c6c6f" test.assert-eq

    # Test decoding
    "576f726c64" from-hex
    test.assert
    "World" test.assert-eq

    # Test case-insensitive decode
    "48454C4C4F" from-hex
    test.assert
    "HELLO" test.assert-eq

    # Test single byte
    "A" to-hex
    "41" test.assert-eq
;