[rabestro]

Fixes #892.

#882 bumped the track to Scala 3.9.0 LTS specifically to unlock binary integer literals, citing secret-handshake as the motivating case. The bump shipped, but nothing used the syntax — grep -rn '0b[01_]\+' exercises/ --include='*.scala' had no matches until this PR.

Why this one exercise

The instructions give the gesture values in binary, while the example gave them in decimal, so checking one against the other meant converting representations:

.docs/instructions.md	.meta/Example.scala (before)
00001 = wink	(1, "wink")
00010 = double blink	(2, "double blink")
00100 = close your eyes	(4, "close your eyes")
01000 = jump	(8, "jump")
10000 = Reverse the order…	reverseGestures = 16

After this change the two line up character for character.

Exercises checked and deliberately not changed

The issue asked for a sweep of other bitwise exercises. Two were close enough to look at:

• allergies — has the same shape (eight power-of-two values combined with &), but its instructions list them in decimal (eggs (1), peanuts (2), … cats (128)). Converting the example to binary would make it diverge from its own spec, which is the opposite of the argument here. Left alone.
• variable-length-quantity — already names its masks (sevenBitsMask = 0x7f, eightBitMask = 0x80). Hex is the right representation for byte masks and it reads fine. Left alone.

So this stays a one-exercise change.

Verification

• bin/test secret-handshake — 11 tests pass.
• bin/verify-exercises-in-docker secret-handshake — exit 0 against the published exercism/scala-test-runner image, so the syntax works in the environment students are graded in, not just locally.

🤖 Generated with Claude Code

[IsaacG]

Eh. The example just shows this exercise can be solved. So long as it works, it doesn't matter too much how it's done :D