All view types in Boost.URL have iterators that store raw pointers
to external data rather than references to the view object itself.
This means iterators remain valid even after the view is destroyed,
satisfying the borrowed_range requirements.
Specializations added for:
- decode_view, pct_string_view
- params_view, params_ref, params_encoded_view, params_encoded_ref
- segments_view, segments_ref, segments_encoded_view, segments_encoded_ref
fix#927
This commit refactors all functions so they have consistent behavior for the space-as-plus encoding option.
- any_params_iter objects store and apply the appropriate option when measuring and copying
- when the option is enabled, encoding functions encode space-as-plus and plus as %2B regardless of the charset
- normalization and comparison algorithms take into consideration special query chars whose meaning changes depending on encoding
- all params_view objects created with default options enable space-as-plus encoding
fix#903
query_rule broke a grammar parse invariant by using different interpretations of the string depending on whether the reason for termination was the end of a string or a continuation with an invalid character.
fix#864
Alan de Freitas