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6.7.4 The boolean type

The two boolean constants are written as true and false. Boolean values are generated by the relational operators. You can use the standard logical operators (&&, ||, !). You can use a boolean type as an argument in an if-then-else expression.

As with C, the logical operators do not evaluate their right-hand sides if their value can be determined just from evaluating their left-hand sides.

                                                      
  true && false == false
  true $\vert\vert$ error "boink!" == true
  if true then 12 else 13 == 12


next up previous contents
Next: 6.7.5 The list type Up: 6.7 Operators Previous: 6.7.3 The character type   Contents
John Cupitt 2004-12-20