function template
<locale>

std::isalpha

template <class charT>  bool isalpha (charT c, const locale& loc);
Check if character is alphabetic using locale
Checks whether c is an alphabetic character using the ctype facet of locale loc, returning the same as if ctype::is is called as:

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use_facet < ctype<charT> > (loc).is (ctype_base::alpha, c)

This function template overloads the C function isalpha (defined in <cctype>).

Parameters

c
Character to be checked.
loc
Locale to be used. It shall have a ctype facet.

The template argument charT is the character type.

Return Value

true if indeed c is an alphabetic character.
false otherwise.

Example

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// isalpha example (C++)
#include <iostream>       // std::cout
#include <string>         // std::string
#include <locale>         // std::locale, std::isalpha

int main ()
{
  std::locale loc;
  std::string str="C++";

  for (std::string::iterator it=str.begin(); it!=str.end(); ++it)
  {
    if (std::isalpha(*it,loc))
      std::cout << "character " << *it << " is alphabetic\n";
    else
      std::cout << "character " << *it << " is not alphabetic\n";
  }
  return 0;
}

Output:

character C is alphabetic
character + is not alphabetic
character + is not alphabetic


Data races

Both loc and its ctype facet are accessed.

Exception safety

Strong guarantee: if an exception is thrown, there are no effects.

See also