casting - Can I assume (bool)true == (int)1 for any C++ compiler?

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asked Oct 17, 2021 in Technique[技术] by 深蓝 (71.8m points)

Can I assume (bool)true == (int)1 for any C++ compiler ?

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1 Answer

深蓝 · Answer 1 · 2021-10-16T22:11:49+0000

Yes. The casts are redundant. In your expression:

true == 1

Integral promotion applies and the bool value will be promoted to an int and this promotion must yield 1.

Reference: 4.7 [conv.integral] / 4: If the source type is bool... true is converted to one.