Adding declarations to std It is undefined behavior to add declarations or definitions to namespace std or to

Allows a function to accept any number of arguments. Indicated by the parameter of the form ... which must appear last in the

constexpr - specifies that the value of a variable or function can appear in

In order to instantiate a function template

"Substitution Failure Is Not An Error" This rule applies during overload resolution of function templates: When substituting the

Allows customizing class templates for a given category of template arguments. Syntax

Appear in any type specifier, including decl-specifier-seq of

Specifies whether a function will throw exceptions or not. Syntax

Allows customizing the template code for a given set of template arguments. Syntax

Reduces (folds)