Angle difference between two bearings

sub infix:<∠> (Real $b1, Real $b2) {
   (my $b = ($b2 - $b1 + 720) % 360) > 180 ?? $b - 360 !! $b;
}

# TESTING
for 20, 45,
   -45, 45,
   -85, 90,
   -95, 90,
   -45, 125,
   -45, 145,
   29.4803, -88.6381,
   -78.3251, -159.036,
   -70099.74233810938, 29840.67437876723,
   -165313.6666297357, 33693.9894517456,
   1174.8380510598456, -154146.66490124757,
   60175.77306795546, 42213.07192354373

  -> $b1, $b2 { say "$b1 ∠ $b2 = ", $b1 ∠ $b2 }

Output:

20 ∠ 45 = 25
-45 ∠ 45 = 90
-85 ∠ 90 = 175
-95 ∠ 90 = -175
-45 ∠ 125 = 170
-45 ∠ 145 = -170
29.4803 ∠ -88.6381 = -118.1184
-78.3251 ∠ -159.036 = -80.7109
-70099.74233810938 ∠ 29840.67437876723 = -139.58328312339
-165313.6666297357 ∠ 33693.9894517456 = -72.3439185187
1174.8380510598456 ∠ -154146.66490124757 = -161.5029523074156
60175.77306795546 ∠ 42213.07192354373 = 37.29885558827