std::messages_base
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                    |   Defined in header  <locale>
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|   class messages_base;  | 
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The class std::messages_base provides a type definition which is inherited and used by the std::messages facets.
Member types
| Member type | Definition | 
 catalog
 | 
An unspecified signed integer type | 
Defect reports
The following behavior-changing defect reports were applied retroactively to previously published C++ standards.
| DR | Applied to | Behavior as published | Correct behavior | 
|---|---|---|---|
| LWG 2028 | C++98 | catalog was defined as int
 | 
defined as an unspecified signed integer type[1] | 
- ↑ The catalog type 
nl_catdused in POSIX messaging API is a typedef of an unspecified type. 
See also
|   implements retrieval of strings from message catalogs  (class template)  |