diff --git a/lexical_cast.htm b/lexical_cast.htm index 4bbdc8e..efc7219 100644 --- a/lexical_cast.htm +++ b/lexical_cast.htm @@ -196,38 +196,60 @@ public: failure.
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Frequently Asked Questions

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Q: Why does lexical_cast<int8_t>("127") throw bad_lexical_cast? -
A: The type int8_t is a typedef to char or signed char. +

Frequently Asked Questions

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Question:Why does lexical_cast<int8_t>("127") throw bad_lexical_cast?
Answer:The type int8_t is a typedef to char or signed char. Lexical conversion to these types is simply reading a byte from source but since the source has more than one byte, the exception is thrown. -

Please use other integer types such as int or short int. If bounds checking + Please use other integer types such as int or short int. If bounds checking is important, you can also call numeric_cast: - 

numeric_cast<int8_t>(lexical_cast<int>("127"));
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Question:What does lexical_cast<std::string> of an int8_t or uint8_t not do what I expect?
Answer:As above, note that int8_t and uint8_t are actually chars and are formatted as such. To avoid this, cast to an integer type first: + 
lexical_cast<std::string>(static_cast<int>(n));
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Question:The implementation always resets the ios_base::skipws flag of an underlying stream object. It breaks my operator>> that works only in presence of this flag. Can you remove code that resets the flag?
Answer:May be in a future version. There is no requirement in [N1973] to reset the flag but remember that [N1973] is not yet accepted by the committee. By the way, it's a great opportunity to make your operator>> conform to the standard. Read a good C++ book, study std::sentry and ios_state_saver. +
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Q: What does lexical_cast<std::string> of an int8_t or uint8_t not do what I expect? -
A: As above, note that int8_t and uint8_t are actually chars and are formatted as such. To avoid this, cast to an integer type first: - -

lexical_cast<std::string>(static_cast<int>(n));
- -

Q: The implementation always resets the ios_base::skipws flag of an underlying stream object. It breaks my operator>> that works only in presence of this flag. Can you remove code that resets the flag? -
A: May be in a future version. There is no requirement in [N1973] to reset the flag but remember that [N1973] is not yet accepted by the committee. By the way, it's a great opportunity to make your operator>> conform to the standard. Read a good C++ book, study std::sentry and ios_state_saver. - -

References

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References