Safe bool idiom
summary
A small experiment replaces the old safe bool idiom with C++11's explicit operator bool and triggers three concrete breakages: expected loss of implicit conversions, failing comparisons against literal 0 unless operator==(..., nullptr_t) overloads are added, and a surprising third case where returning a pimpl-held testable type no longer converts because return does not perform explicit conversions. A minimal patch compiles client code nowhere — the fix is local casts or API workarounds, so the library keeps the old idiom for compatibility.
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chapters (6)
- 0:00Start
- 1:16Without the Safe Bool Idiom struct Testable
- 3:21implicit conversions
- 3:51comparison against literal 0
- 4:58return statements
- 5:46Solution: must change the code
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