10 REM A truth value carries its payload in boolvalue, not floatval. The three
20 REM numeric operators were `if ( INTEGER ) ... else <treat as float>`, and
30 REM that else was a catch-all, not a float branch -- so a truth value
40 REM on the LEFT computed 0 - 1 into a field nothing reads, kept its BOOLEAN
50 REM type, and printed `true` instead of -2. Silent, and wrong twice over.
60 A# = 1
70 PRINT (A# == 1)
80 REM On the RIGHT it stays legal and stays -1, the same property that
90 REM lets AND and OR double as logical operators. Refusing it would have
100 REM broken every condition in the language.
110 PRINT 5 - (A# == 1)
120 PRINT 5 * (A# == 1)
130 PRINT 5 + (A# == 1)
140 PRINT 4 - (A# == 2)
150 REM And on the left it is refused by name rather than computed.
160 PRINT (A# == 1) - 1