Why is std::string implemented as basic_string of `char` and not `unsigned char`

Question

typedef basic_string<char> string;

All the std::string facilities in the standard library are using char. Why is that? Although all the characters of the ASCII table (128) fit into the range of a char (-128 to 127), many other character encodings are using 8-bits for representation.

What is the advantage of having 'negative' values in a string of chars?

just a side note: `char` can be signed or unsigned, it isnt specified by c++ — 463035818_is_not_a_number, May 14 '17 at 11:36
related: http://stackoverflow.com/questions/17097537/why-is-char-signed-by-default-in-c — 463035818_is_not_a_number, May 14 '17 at 11:38
the question isnt a dupe, but [this answer](http://stackoverflow.com/a/17097575/4117728) has a quote that more or less answers also your question — 463035818_is_not_a_number, May 14 '17 at 11:42
`char` can be either signed or unsigned, and might contain more than 8 bits, and ASCII isn't a requirement either. Whatever works best on the system you use. — Bo Persson, May 14 '17 at 13:53

score 2 · Accepted Answer · answered May 14 '17 at 12:02

2

String literals are of type const char*, so it would require a O(n) conversion when doing std::string("fooo").

answered May 14 '17 at 12:02

Jean-Michaël Celerier

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Why is std::string implemented as basic_string of `char` and not `unsigned char`

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