7.5 Mixing Scopes

Subformat specifier formatting directives change the current set of interpreted formatting directives. Accessing formatting directives from broader formatting directives interpretation scopes is possible via back scoping formatting directive syntax. The formatting directives for which the introducing % sign is immediately followed by a : (`colon') sign, a decimal string and an other : (`colon') sign are interpreted in the formatting directives interpretation scopes indicated by the parent order indicated by the decimal string. The parent order indicates how many formatting directives interpretation scopes should be descended for formatting directive interpretation (if it is 1, the currently interpreted formatting directive is interpreted in the parent scope of the current formatting directives interpretation scope, if it is 2, the currently interpreted formatting directive is interpreted in the parent scope of the parent scope of the current formatting directives interpretation scope and so on).

See Format Specification Syntax.

Whenever the data formatter enters a back referenced formatting directives interpretation scope during formatting logic execution it calls the application formatting context set_scope method.

Whenever the data formatter exits a back referenced formatting directives interpretation scope during formatting logic execution it calls the application formatting context get_scope method.

See x1f4_run_format6.

See struct x1f4_f6link_type.

The rank of the formatting directives interpretation scope in which the formatting directives are currently interpreted is passed the application formatting context set_scope and get_scope methods as their second argument. The formatting directives interpretation scope rank is 0 based, with the outmost broader formatting directives interpretation scope ranking 0, its children 1 and so on.